Ketogenic Diet

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Although the modified Atkins diet (MAD) described in this document has been extensively used and studied in children with other disorders (for example, epilepsy), its use for those with Prader-Willi syndrome (PWS) has not been tested in clinical trials and its efficacy and safety for those with PWS has not been determined. It is therefore essential that use of the MAD for someone with PWS be supervised by a medical doctor. Do NOT try to use this diet without first discussing it with your child's doctors and, at minimum, obtaining their agreement to monitor the diet. It is also important that all other health care providers (dentists, etc.) are also informed that the child is on the MAD. Parents must purchase and use a blood glucose and ketone meter (the same as used by diabetics) along with sufficient glucose and ketone testing strips before starting the diet in order to monitor the child's metabolic response to the MAD. Such monitoring is especially important when the child is sick and if they are pre-diabetic (insulin resistant) or diabetic.

Low carb diets such as MAD may reduce the need for medications prescribed for insulin resistance and diabetes such metformin and insulin and it is essential that you work closely with your child's pediatrician and/or endocrinologist so that the dosages of such medications can be appropriately adjusted if needed. Never, ever reduce or stop any of your child's medications without first consulting with your child's doctors, no matter what you've heard from other parents or read on the internet.

The child's pediatrician, endocrinologists and other specialists must be told about the diet prior to drawing blood for laboratory work so that they can choose the best tests to monitor the child's health and metabolism.


This document represents our best understanding of how a modified Atkins diet (MAD) can be used to help children with PWS. It is primarily meant to be a tool for parents and is, therefore, not fully referenced. It is based upon a great deal of reading and thinking and observation.

Initial observations came from dietary modification of a 9-year-old boy with PWS. He has been on a relatively high fat diet from birth. Starting at age three, he went grain and sugar free, still with liberal use of fats. At age 7 he went on MAD and established a state of ketosis with blood ketones of approximately 2 mmol/L. He is largely a typically developing 9 year old boy who blends with his peers at school, in the gym, and in recreational activities.

A now almost six-year-old girl has followed a similar diet with no grains or sugar and liberal use of fat (in particular coconut oil) since age 10 months. She is not on MAD, but was just recently tested to have blood ketones of 0.5 mmol/L. She has entered kindergarten with her non-PWS peers and blends with them at school and in recreational activities. She is generally considered to be a child with a lot of energy.

This summer, several children of varied ages (1-9 years) have given up sugar and grains and increased their fat consumption. In some cases, the parents have opted to put their child on MAD and documented blood ketone levels of 2-4 mmol/L. In all cases that we know of, the parents have been very impressed with the results. The most common observations are increased energy, decreased hunger, and developmental leaps.

Most PWS experts recommend an extremely low calorie, low fat diet for children and adults with PWS. Those guidelines are well-established and it is easy for parents to find support in implementing them.

MAD represents a paradigm shift in the feeding and treatment of children with PWS. As such, any parent who decides to make the shift to MAD should be aware that the verdict is still out as to whether or not it represents a superior approach to nurturing the mind and body of a child with PWS.

MAD is prescribed successfully for children with epilepsy. Therefore, there are physicians (pediatricians and specialists) and dieticians who are familiar with the diet and can provide guidance. Unfortunately, it may be difficult to find physicians or nutritionists in the PWS field who can support our patient population. This guide is meant to bridge that gap for parents who would like to try an alternative nutritional approach to feeding a child with PWS. It may also help doctors who are unfamiliar with MAD to understand it better. We have included links below to assist parents in finding a doctor and dietitian who may be able to support them in trying MAD for their child.

Basic Elements

MAD is not a calorie-restricted diet. As long as the child is of normal weight, there is no need to limit calorie intake.

There are three basic elements to using MAD for PWS.

(1) Make sure that the child gets plenty of fat throughout the day. Any fat will do although excessive use of seed oils (e.g., corn oil) with large amounts of omega 6 fatty acids should be avoided. Many parents use coconut oil, olive oil, butter, and heavy whipping cream. The child will be burning the fat as their main energy source in MAD.

(2) Make sure the child gets adequate protein. It is always best to consult with your pediatrician or a dietitian to determine the amount of protein that your child needs. You can also use the USDA's online calculator at It is okay to go a bit higher (10-20%) than the USDA recommendations.

(3) Restrict carbohydrates to the level at which the child can consistently maintain a moderate level of ketosis. This will likely require elimination of sugars and grains and replacement of high glycemic index fruits and starchy vegetables with more keto-friendly alternatives. While optimal target blood ketone levels in PWS are not known, we suggest that parents aim for a moderate level of ketosis with blood ketones of 2-4 mmol/L as measured by blood ketone meter. Note that although urinary ketone test strips such as Ketostix can provide a general indication of whether or not the child is in ketosis, they are not accurate enough to properly monitor the actual level of ketones. Urinary test strips therefore should not be used as a substitute for a blood ketone test meter and especially should not be relied on for monitoring ketosis during sickness or in those with pre-diabetes or diabetes.

Dietary Suggestions

Low glycemic index fruits include most berries and some melons. Bananas, oranges, and apples are likely to be too sugary for this diet. Carbohydrate consumption should be spread out throughout the day's meals and snacks. If a child receives a full day’s allotment of carbohydrates at once, s/he is likely to be kicked out of ketosis and hunger may increase dramatically.

Carbohydrates should always be given with a fat source, for example,: strawberries and cream, tomatoes and olive oil, blueberries and full fat ricotta cheese.

Non-starchy, low glycemic index vegetables include greens, broccoli, cauliflower, and peppers. Potatoes, sweet potatoes, and carrots are likely to be too sugary for this diet.

Protein intake should be robust because the body uses protein to build and maintain muscle. Fatty cuts of meat work well on this diet: chicken with skin, salmon, hamburger. Do not use low fat meats (e.g., skinless chicken or turkey breast) unless you add additional fat to the meal.

Snacks are perfectly fine. Good MAD snacks include avocado, hardboiled egg, deviled egg, ketocandy, and coconut milk.

While sugar substitutes are allowed in MAD, their role in hunger/satiety in children with PWS is largely unexplored. Parents have had the most success using stevia, and possibly sugar alcohols such as erythritol. Note that although the U.S. FDA allows sugar alcohols to be listed as having no carbohydrates, they are in fact metabolized as sugar at a rate approximately 50-60% as that of sugar and so that must be taken into account.

MAD often suppresses appetite. Children may not want to stay and finish every meal. That is okay, but they should, at a minimum, eat some fat at each meal.

Some children may be hungry after finishing a meal. That is okay. Extra servings of MAD vegetables with fat should be fine on this diet. However, if the child does not report feeling full after eating an excessive amount, then typical PWS behavioral modification may be needed.


A diet tracking and analysis program should be used make sure the child has adequate vitamin and mineral intake as well as to track carbohydrate, fat, and protein intake. Many parents use DietOrganizer at

All supplements and medications need to be carefully evaluated for carbohydrates. Sugars and starches may be hidden in the ingredient list with non-obvious names. It may be necessary to ask a pharmacist or call the manufacturer to establish that a supplement or medication is truly keto-friendly. The Charlie Foundation maintains a list of keto-friendly personal care products and OTC medications at

There is some anecdotal evidence that supplementation with vitamin B12 and iron may improve the response to the MAD. Many parents seem to have the most success with Gentle Iron (ferrous bisglycinate) and vitamin B12 shots.

Carnitine transports fat into cells so that it can be used as fuel. Children on MAD may need carnitine supplementation to maximize use of fat as fuel. Blood carnitine levels can be checked by a health care provider. Physicians can prescribe carnitine or carnitine can be purchased as a nutritional supplement. Prescription carnitine often contains sugar and is therefore not appropriate for a child on MAD. Carnitine dosing is typically 50 mg per kilogram of weight per day (50 mg/kg/day). Some parents have found that the carnitine fumarate form of carnitine is more effective than other forms.

In many cases, children going on MAD will naturally reduce their fiber intake. This transition may be challenging for the gut. Probiotics may be helpful. The Culturelle kid packet has been recommended for kids on a ketogenic diet.

It is important that all of your child's health care providers know about your child's supplements.


In general it is best to gradually introduce the MAD, for example, by reducing daily carb intake by 5 grams, testing blood sugar and ketones after a day or so, then reducing daily carb intake by another 5 grams if the child is not yet in ketosis or ketosis is relatively minor (that is, between 0.5 to 1.0 mmol/L).

It may take 4-8 weeks for the body and brain to reach maximal efficiency at using fats and ketones for energy. This process is referred to as keto-adaptation. Breaking MAD for pizza or birthday cakes will likely delay this process considerably. Consistently low carbohydrate/high fat throughout the day, every day is important. It may be that keto-adapation will not occur if there are many exceptions.

Early observation suggests, however, that kids with PWS adjust to MAD very easily. Their bodies apparently prefer to burn fat for fuel and they appear to slip into ketosis more easily than would be expected based upon observation of children with epilepsy being treated with MAD.

Children with PWS may relish the decreased hunger and more stable moods that they experience on MAD. The child’s preference for the diet can really help with compliance. It is also possible to search online for ketogenic recipes and, with some creativity and effort, make “substitutes” for many of the child’s favorite treats.

Maintaining MAD

A child on MAD is reliant on burning fats as fuel for their body and brain. A genetically typical child can obtain these fats from food or from stored fat. It appears that children with PWS are not always easily able to access and burn their own fat as an energy source, for example, during long bouts of vigorous play. This may mean that a keto-adapted child with PWS may have an “energy crash” similar to hypoglycemia if dietary fat is not provided throughout the day. The child will literally sit down, turn pale, and have difficulty communicating. He or she may become belligerent. The situation is quickly reversed by feeding fat (literally a teaspoon full of olive or coconut oil or tiny cup of heavy cream).

As more children with PWS enter ketosis we will develop a better understanding of what is happening during such an energy crisis and what can be done to prevent it. For now, children who experience this crash will need small dietary infusions of fat (e.g., avocado, ketocandy, teaspoon of oil, etc.) every few hours or so. The amount of time between such fat infusions may depend on the child’s activity levels. Days of active play may be more demanding for a child than sedentary days.

Monitoring MAD

The child's pediatrician, endocrinologists and other specialists must be told about the diet prior to drawing blood for laboratory work so that they can choose the best tests with which to monitor the child's health and metabolism. All parents using the MAD for a child with PWS need to obtain a blood glucose and ketone testing device (the same as those used by diabetics) prior to starting the diet. This is important for all children with PWS, not just those with pre-diabetes (insulin resistance) and diabetes. There is no reason that we know of to aim for “deep ketosis.” Blood ketones of 2-4 mmol/L are relatively modest and we know of no reason to try to go higher than that. Blood ketones above 7.0 mmol/L are not normal and indicate that the child may have a problem with inadequate insulin production (insulinopenia) that in turn may lead to the development of diabetic ketoacidosis (DKA). DKA can be the first indication of diabetes and is a potentially life-threatening medical emergency. If your child has blood ketones above 7.0 mmol/L along with high blood glucose (>200 mg/dL), it is imperative that you seek immediate medical attention. This is especially true if the child also has lethargy, unusual sleepiness, mental confusion, frequent drinking of large amounts of fluids, and/or frequent urination,

In the beginning, blood glucose and ketones should be measured daily first thing in the morning before breakfast and approximately one to 1-1/2 hours after breakfast. Once the child has reached a relatively stable level of moderate ketosis and you are comfortable with the diet, the testing interval can be increased, for example, to once a week. Blood and ketone testing should be increased during sickness (e.g., bacterial and viral infections), especially if the child's food intake is decreased and they become lethargic, unusallyunusually sleepy, or mentally confused.


Keto Kid. Written by Dr. Deborah Snyder, DO, published by Demos Medical Publishing, New York, N.Y. Published 2007.

The Keto Cookbook: Innovative Delicious Meals for Staying on the Ketogenic Diet. Written by Dawn Marie Martenz and Laura Cramp, RD. Published by Demos, 2011.

The New Atkins for a New You. Written by Eric C. Westman, MD, Stephen D. Phinney, MD, PhD, and Jeff S. Volek, PhD, RD. Published 2010.

The Art and Science of Low Carbohydrate Living. Written by Jeff S. Volek, PhD, RD and Stephen D. Phinney, MD, PhD. Published 2011.

Amazing Adventures of Ayden Jane (

The Charlie Foundation (

Matthew's Friends (

ASweetLife Recipes (

The following links may assist parents in finding a doctor and/or dietitian to support them in using the MAD -

Worldwide list of Physicians with Expertise in the Ketogenic Diet at -

Ketogenic diet centers for children with epilepsy in the U.S. and Canada at -

Kid Stories


Dean is in his second year of a special ed. Pre-K class (he is 4 and they start at 3). His teacher is the same as last year and she is awesome. She has always believed in Dean while still being aware of his difficulties. We had our first home meeting (they do one a month) and she said, "this is not the same kid I had at the end of last school year. He is so much more focused, is problem-solving better, has more energy..." and went on to describe all the improvements in motor skills and speech. She's bumped up his recommendation for next year to be out of the special ed. class a little more and to put him in the "mild" special ed. class instead of the "moderate" class. It's only September! It was so great to hear someone else who has known Dean for a while and sees him all the time to comment on these changes. Yay for keto!


Cole is 6 and just started first grade. Already getting rave reviews from Coles teachers and therapists of Coles performance, energy level and focus at school in comparison from last year!!! We started this diet mainly to increase his energy level and everything else is a such an amazing bonus! We have not started the more involved diet of charting and seeing if he is in ketosis yet but I can't even imagine how much better he will be.... We meet with our dietician on Friday!!


So, Aerin is just a week short of her 18 month birthday. She's been making slow, but steady, progress since she was born. After she turned one, however, she seemed to just stall out. Our particular challenge has been with gross motor. She just couldn't seem to get past rolling and sitting and by the end of August, even crawling still seemed weeks away. Well, on Labor Day weekend (so about two weeks ago) my husband and I decided to start putting some of the things we've been reading here into practice. We started her on iron (first with Poly Vi Sol and then switching to Gentle Iron) and added coconut oil (3-4 tsp per day). She's never really eaten grains or sugar but we started watching carbs through fruits and veggies--not really reducing them as much as just keeping an eye on them. She still takes about 20 ounces of whole milk (her largest source of carbs at the moment) but we've started cutting it with almond or coconut milk to begin weaning her off. And we've pushed fats. Avocado, buttered veggies, cream in her omelet--that sort of thing. Well, last week, she just up and decided to start commando crawling! Plus her receptive AND expressive language have just blossomed. It's hard to describe how huge this feels because it's hard to effectively communicate how stuck she seemed before, but she is like a different kid. I've thought about it a great deal, trying to logically attribute the gains to the right place and the best I can come up with is that the fats and the supplements have somehow formed the key that unlocked her trapped potential. Someone mentioned "improved executive functioning" and this sounds like the more scientific answer for what I see happening in her. It's like all of these connections with the world around her are forming in her brain and she can, all of sudden, really participate in it. I just wanted to share and thank everyone on this site for all that you have done to forge a new path in treating PWS. And thank you for taking the time to share it with the rest of us. We still have a lot of work to do, but I am excited about what the future looks like!


Last week we began our journey to cut out grains and boost fats. I will say in just the past week I have noticed a big change with homework and her ability to still have a good energy level for her late afternoon activities (dance and horses) and therapy. Maya is 6 and in 1st grade. She usually has spelling, reading and math homework every night (ridiculous.) After a long day of school, she would come home have a snack and need to veg for a half or so before starting homework. Then it would normally take a solid hour to get her to focus, stay alert and not get frustrated (mainly with handwriting.) Well this week she came home full speed ahead, talking about all her homework and wanted to start right away, after a keto-chocolate of course! She did her addition homework and wrote her spelling words all on her own and was done in 30 minutes. Then, still had plenty of energy for activities! Her OT commented both last week and this week how she has been "on fire!" YAY!

I forgot to mention we also gave her a b12 shot and for the first time in almost a year, she responded and I noticed change!! You had mentioned before that the extra increase in fats might help, I think it did!!

Older Child

Our daughter is 12 and does not have any weight/hunger issues. We have never eaten the standard American/British diet and she has been on various supplements since 4 months of age(GH at 6 months of age).

She went gluten free a while ago and has told us that she no longer feels as 'fuzzy' since giving up gluten. Since my goal for her is to have a completely independent adult life we decided to give the ketogenic diet a try. Our daughter tests her urine and she is in ketosis. However, we aren't seeing the benefits that others have seen. Last night we were chatting about if she feels 'sharper' since starting this new eating plan (she refuses to call it a diet). She told us that she doesn't feel any different except that she may have a bit more energy. We decided to give the ketogenic diet another 4-6 weeks-if after that time she doesn't feel any better, and we (along with her teachers) don't see an improvement then we will go back to just being low carb/gluten free with a focus on good fats.

As of today she is on a probiotic, omega 3 (high in EPA), iron, methyl B12, carnitine fumerate, CoQ10. In the winter we will add D3. I'm toying with the idea of putting her back on TMG.

Over the years we have been on various forms of CoQ10, various formulations of omega 3's, different types of carnitine, nutrivene (PWS formula with lower levels of vitamin A and E), calcium, magnesium, zinc, creatine, carnosine, TMG, folic and folinic acid... I'm sure I'm leaving something out. I was so lucky in that our pediatrician in Texas was wonderful in working with me to help my daughter be the best she can be. For the past 8 years I've been doing it all on my own which is quite scary. I lurk on the message boards, go off and do my own research.

I've completed a food diary but haven't determined carbs/fat/protein. I also wanted to add that everything I do food and supplement wise is discussed with my daughter. I feel that it is important for her to be on board with what I am doing. If she has an objection (which she hasn't so far) then I would respect her wishes.

Track Diet

Diet software for calorie counting and weight loss - DietOrganizer

Please note that you want the Windows or Mac -desktop- version, NOT the iPhone version because it doesn't track vitamins and minerals. Unfortunately, it also doesn't sync with the PC versions.


We have just started using medium chain triglyceride (MCT) oil. It is isolated from coconut oil and is the component of coconut oil that is responsible form kicking kids into ketogenesis. It can be purchased in health food stores or online.

First Story

As far as I know, my boy (age 9, 70 pounds) is the first kid with PWS to be given MCT oil and I am just now experimenting with it. We started with 1 teaspoon a day, the next day we did 2, the next day 3, and today we are trying 4. The teaspoons are spread out throughout the day. Oneida has pointed out that I am cranking it up too fast (pointed noted). It is hard for me to resist, though, because it seems to be having an incredible effect on him - as if it is his perfect fuel.

It also seems to be giving him about a 0.5 - 1 point boost in ketones, FWIW. Normally his blood ketones are < 2 in the morning. We gave him 1 teaspoon of MCT before bed and the next morning he was at 2.4. We gave him a dose of MCT at 10:15 and measured him at 10:45. He was at 1.8. When we measured at 11.45, he was at 2.7. He loves the feel of his brains on MCT. He is processing quickly and having big thoughts and talking a mile a minute. He is more stable and seems to be thinking less about food. It is very interesting. I will post more as I observe more.

3 weeks later

He has grown ¾ inch in 6 weeks! He is now (finally!) at the 50th percentile for height. Note that Dr. Miller did not increase his GH this spring so this major growth spurt happened in the absence of a boost in GH. I think that this huge growth spurt was due to the MCT oil (1 tablespoon in the morning for the past few weeks). To be honest, I think he grew this much in the past 3 weeks.

He has also gained weight. He has been hungry and we have been feeding him more. Not really PWS hungry, but hungry like a kid who is growing like crazy. Unfortunately, his body isn’t good at figuring it all out. So, while he is at 50th percentile for height, he is now at the 75th percentile for weight. This isn’t horrible, but it is something we have to keep an eye on. He had a bit of a belly today at the doctor’s office.

He has gained a grade in reading level. He is revisiting math that was too hard for him at the beginning of the year and now it is "easy." He says that his body moves better and he has more stamina - his muscles don't hurt as much after multiple repetitions.

He goes hard all day - school, karate, and a high school theatre production. When he comes home he is full of thoughts and talking. He reads or does arts and crafts and then just crashes. I think that his body is working very hard.

Two Year Old Story

Also one teaspoon of MCT oil was like 10 shots of espresso for our 2.5 year old! Plan on playing with the .5 teaspoons over the weekend to determine how to use this new rocket fuel to our advantage. Five minutes after snack with 1 teaspoon of MCT oil mixed in he ran up and down our large hill for a total of 1/4 mile. I was worn out!

For him at 26 lbs one teaspoon was good about 2, 2.5 hours. Today I did two 1/2 teaspoons and it was much less dramatic, but he didn't nap at all through a day of home, babysitter, speech, park and long walk (school closed today). Normally he would have napped at least one hour. More verbalizing than normal today too. Good solid jumping off a high curb.

Dean Story

Dean is 4 years old, 40 pounds, and we have been giving him a tsp. of MCT oil a day. (assuming that the whole tsp. gets into him). Dean has gained more in the last few weeks speech-wise than he has in probably two years. He also has a new SLP who is *fantastic,* although we started seeing her in July. So still. I sat in on his speech session today and couldn't even believe what I was hearing. He has a VERY long way to go, but if the pace can continue like this, that will be really helpful. I think it's clear that his brain likes fat! Only question is with this MCT oil... his GAS is just out of control.

Actually, I would definitely describe it as a bit of a plateau, but absolutely at a higher level. What's freaking me out the most is how Dean's receptive language is improving. Either it was there all the time and he just couldn't let us know how much he was understanding, or it's just awakening stuff he couldn't even access? I don't know. Like others have said, it's almost creepy, so I'll take the plateau for a bit. Then onward and upward we go.

Well, we've been pretty strict about limiting carbs and have been pushing fats, particularly coconut oil and MCT oil. Supplements are gentle iron, B12 injection every other week, Nordic Naturals omegas, carnitine fumarate, electrolyte packet, multivitamin, and then his regular meds. Dean is eating a LOT of food (just as much as my other boys if not more!) and he is still really lean.

Fluid Loss

No, it's different from dehydration and has to do with the natural diuretic effect of low carb diets. I'll try to explain.

Higher carbohydrate diets where blood sugar and insulin commonly spike after meals cause a considerable amount of water retention in the body through 3 mechanisms -

(1) The body stores excess dietary carbohydrates in two main ways - as fat in fat cells and as glycogen in muscles (up to 300 grams in adults depending on muscle size) and the liver (around 100-120 grams in adults). Glycogen is stored in liver and muscle cells along with water at a rate of around 3-4 grams of water for every gram of glycogen.

(2) In addition, the elevated insulin levels typical of excessive carbohydrate intake cause water retention by inhibiting sodium excretion by the kidneys.

(3) The chronically elevated insulin levels associated with excessive carb intake also cause chronic subclinical inflammation throughout the body and brain which in turn also causes water retention (similar to how one's throat becomes swollen when it is inflamed by a strep infection).

When carb intake is significantly restricted as with a ketogenic diet, all of that excess water is released for elimination by the kidneys, for example, as glycogen stores are used for energy production, the associated water is released for elimination by the kidneys as urine. Similarly, as chronically elevated insulin levels drop due to reduced carb intake, more water is released for elimination because insulin is no longer causing the kidneys to hold onto too much sodium, and even more water is released when the systemic inflammation caused by chronically elevated insulin is reduced.

Electrolytes such as sodium and potassium are also lost in urine when all of that excess water is released and turned into urine by the kidneys. It can sometimes happen that too much sodium and potassium are lost if a large amount of excess water is released over a short period of time, for example, when someone who is overweight and insulin resistant radically changes their diet overnight from high carb intake to just 10-20 grams of carbs per day. The resulting electrolyte imbalance can cause symptoms such as foggy thinking, fatigue, sleepiness, muscle weakness and cramps, headache and nausea that low carb dieters call "keto flu." Parents starting children on the modified Atkins diet (MAD) therefore need to carefully monitor the child for those symptoms, especially during the first week and if the child was previously on a relatively high carb diet. Ensuring that children have adequate electrolyte intake is one of the reasons why I keep suggesting that parents use a diet tracking and analysis program.

"Keto flu" can be avoided (and of milder cases treated) by replenishing electrolytes, especially sodium. Ways to do that include -

  • Drinking 1-2 cups of bouillon each day during the first week or so when starting the MAD.
  • Using moderate amounts of salt and/or a potassium chloride salt substitute such NoSalt, LoSalt, Lite Salt, AlsoSalt, etc. on food. (Note that those with kidney or heart failure or diabetes should not use salt substitutes except under medical supervision.)
  • Electro-Mix ( is zero carb and comes in individual packets of powder that are mixed with water (I mix it in a 20 oz water bottle) and provide a good amount of potassium as well as some calcium. I usually add 1/4 tsp of salt to it. Lara reports that Kian doesn't like it, I find it smells more lemon-lime than it tastes and can be mixed with other things without noticeably affecting their taste.
  • Regular V8 juice has a good amount of both sodium and potassium, I use it diluted 1:4 with water (i.e., 4 oz of V8 juice with 16 oz of water) and sip it throughout the day.
  • Low sodium V8 juice replaces some of the salt in regular V8 juice with potassium chloride, so it is a great source of potassium. I usually add about 1/4 tsp of regular salt to increase its sodium content. (I live in the desert where getting enough salt is especially important during the summer.)
  • Avocados are a great source of potassium.
  • Magnesium supplements can be used if diet analysis shows that its intake is low.

Bone Density

Epilepsy itself is a recognized risk factor for osteopenia, osteoporosis, and even rickets. Possible reasons for that include reduced physical activity and less sun exposure due to epilepsy-related disability as well as the negative effects that many anti-epilepsy drugs (AEDs) have on bone metabolism. (see abstracts below) Children on the classic ketogenic diet (KD) for epilepsy have typically been on high doses of multiple AEDs and many continue to need AEDs as add-on therapy to the KD.

As far as I can determine, no study has looked at the effects of the modified Atkins diet (MAD) on bone health in children. (There is a 3-month study (see below) that found an Atkins-style diet did not increase bone turnover in adults but its applicability to children with PWS is uncertain at best.) That said, as you have found, it has been well recognized for quite some time that the classic KD for epilepsy can cause osteopenia in children (as well as slow growth). There are a several possible reasons for that.

1. The classic KD for epilepsy is specifically designed to maximize ketosis. Ketones are acidic and the body must therefore buffer that acidity with bicarbonate (listed as carbon dioxide in comprehensive metabolic panels (CMP)) and, if that runs low, alkalizing minerals such as calcium and potassium. It has been theorized that mild acidosis is one of the mechanisms by which the KD suppresses seizures and so mild acidosis in children with epilepsy on the classic KD has not been aggressively addressed in the past although that is changing now with the more routine use of potassium citrate (Polycitra-K) as an alkalizing agent.

2. The multivitamin/mineral supplement typically used in the KD for epilepsy is a one-a-day type that only contains the RDA for calcium, vitamins D and K, etc., which I don't think is sufficient to meet the specific nutritional needs of children on the medical KD. For example, the RDA for calcium is based on healthy children who aren't ketotic and therefore don't have the possible sink of calcium being used to buffer the mild acidosis that can occur on the classic KD for epilepsy.

3. In order to keep gluconeogenesis at a low level, the classic KD specifically restricts protein to the minimum needed to keep the child slowly growing as slow growth is considered an acceptable trade off for children whose brains are being destroyed by refractory seizures. Adequate dietary protein is essential for bone health (see below) and so the low level of protein in the classic KD is probably another factor in the reduced rate of bone formation. Low protein diets cause a reduction in intestinal calcium absorption that is accompanied by secondary hyperparathyroidism. Dietary protein increases circulating IGF-1 (which has anabolic effects on muscle and bone) and also increases calcium absorption, so the more adequate protein intake with the MAD will be better for bone health than the classic KD for epilepsy.

In other words, there are important nutritional and other differences between children with epilepsy who are on the classic KD and children with PWS who are on the MAD. That does not mean that there won't be a problem with bone health in children with PWS who are on the MAD, only that there is more to consider than just that the classic KD for epilepsy and the MAD are both ketogenic diets.

Osteopenia and osteoporosis are reported in PWS although recent studies suggest that bone mineral content and density are normalized by GH treatment in PWS. It is not clear how much of the poor bone mineral content and density in PWS is actually due to something inherent in PWS and how much is due, for example, to a low protein and otherwise nutritionally inadequate diet and reduced activity levels and sun exposure due to the person being severely overweight and/or "low energy" because they're on what is essentially a starvation diet. It could be that increased protein intake on the MAD compared to the severely restricted diet typically used for PWS and increased activity and sun exposure due to improved energy levels on the MAD will improve bone health in PWS. Also, like every other physiological process, bone metabolism requires adequate cellular energy and so improved cellular energy metabolism on the MAD could improve bone formation and maintenance in PWS.

However, it could also turn out that the MAD does adversely affect bone health in PWS, at this point we just don't know. As is all too often true with PWS, there is no clear answer to your question. In general, monitoring of bone health is indicated for every child with PWS, regardless of whether they are on the MAD or not, and every child on the MAD needs to be followed by a doctor, registered dietitian, and/or other knowledgeable health professional. I would also really like every parent using the MAD for a child with PWS to use a diet tracking and analysis program in order to ensure adequate intake of vitamins K and D, calcium, potassium, magnesium and other micronutrients that are important to bone health. And obviously we need studies to determine not only the efficacy of the MAD for PWS but to also identify any possible adverse effects.

Semin Pediatr Neurol. 2007 Dec;14(4):196-200.

  • Bone consequences of epilepsy and antiepileptic medications.* Samaniego EA, Sheth RD.

Department of Neurology, University of Wisconsin-Madison, Madison 53792-5132, USA.

Childhood and adolescence are critical periods of skeletal mineralization. Peak bone mineral density achieved by the end of adolescence determines the risk for later pathological fractures and osteoporosis. Chronic disease and medication often adversely affect bone health. Epilepsy is one of the most common neurological conditions occurring in persons under the age of 21. Epilepsy may affect bone in a number of ways. Restrictions of physical activity imposed by seizures, cerebral palsy or other coexisting comorbidities adversely affect bone health. It has been observed that treatment with phenytoin and phenobarbital can be associated with rickets. More recently, established agents such as carbamazepine and valproate have been shown to be associated with decreased bone mineral density. The literature related to bone health in pediatric epilepsy is reviewed.

Clin Neurol Neurosurg. 2010 Jan;112(1):1-10.

  • Bone and calcium metabolism and antiepileptic drugs.* Verrotti A, Coppola G, Parisi P, Mohn A, Chiarelli F.

Department of Pediatrics, University of Chieti, Italy.

There is increasing evidence suggesting that epilepsy and its treatment can affect bone mineralization and calcium metabolism. Many studies have shown a significant reduction in bone mineral density in patients treated with classic (phenobarbital, carbamazepine, valproate, etc.) and with new (oxcarbazepine, gabapentin) antiepileptic drugs. In spite of data about the possible effects of the antiepileptic drugs on calcium metabolism, the mechanisms of this important side effect remain to be defined. The abnormalities of calcium metabolism were thought to result from the cytochrome P450 enzyme-inducing properties of some antiepileptic drugs and the resultant reduction in vitamin D levels, but the effect of many medications (e.g., valproate) cannot be readily explained by vitamin D metabolism. In this article, the literature related to the effects of classic and new antiepileptic drugs on bone health and calcium metabolism is reviewed.

Int J Vitam Nutr Res. 2011 Mar;81(2-3):134-42.

  • Protein intake and bone health.*

Bonjour JP. Division of Bone Diseases, University Hospitals and Faculty of Medicine, Geneva, Switzerland.

Adequate nutrition plays an important role in the development and maintenance of bone structures resistant to usual mechanical stresses. In addition to calcium in the presence of an adequate supply of vitamin D, dietary proteins represent key nutrients for bone health and thereby function in the prevention of osteoporosis. Several studies point to a positive effect of high protein intake on bone mineral density or content. This fact is associated with a significant reduction in hip fracture incidence, as recorded in a large prospective study carried out in a homogeneous cohort of postmenopausal women. Low protein intake (< 0.8 g/kg body weight/day) is often observed in patients with hip fractures and an intervention study indicates that following orthopedic management, protein supplementation attenuates post-fracture bone loss, tends to increase muscle strength, and reduces medical complications and rehabilitation hospital stay. There is no evidence that high protein intake per se would be detrimental for bone mass and strength. Nevertheless, it appears reasonable to avoid very high protein diets (i. e. more than 2.0 g/kg body weight/day) when associated with low calcium intake (i. e. less than 600 mg/day). In the elderly, taking into account the attenuated anabolic response to dietary protein with ageing, there is concern that the current dietary protein recommended allowance (RDA), as set at 0.8 g/kg body weight/day, might be too low for the primary and secondary prevention of fragility fractures.

Am J Clin Nutr. 2008 May;87(5):1567S-1570S.

  • Amount and type of protein influences bone health.* Heaney RP, Layman DK.

Creighton University, Omaha, NE, USA.

Many factors influence bone mass. Protein has been identified as being both detrimental and beneficial to bone health, depending on a variety of factors, including the level of protein in the diet, the protein source, calcium intake, weight loss, and the acid/base balance of the diet. This review aims to briefly describe these factors and their relation to bone health. Loss of bone mass (osteopenia) and loss of muscle mass (sarcopenia) that occur with age are closely related. Factors that affect muscle anabolism, including protein intake, also affect bone mass. Changes in bone mass, muscle mass, and strength track together over the life span. Bone health is a multifactorial musculoskeletal issue. Calcium and protein intake interact constructively to affect bone health. Intakes of both calcium and protein must be adequate to fully realize the benefit of each nutrient on bone. Optimal protein intake for bone health is likely higher than current recommended intakes, particularly in the elderly. Concerns about dietary protein increasing urinary calcium appear to be offset by increases in absorption. Likewise, concerns about the impact of protein on acid production appear to be minor compared with the alkalinizing effects of fruits and vegetables. Perhaps more concern should be focused on increasing fruit and vegetable intake rather than reducing protein sources. *The issue for public health professionals is whether recommended protein intakes should be increased, given the prevalence of osteoporosis and sarcopenia.*

J Am Coll Nutr. 2005 Dec;24(6 Suppl):526S-36S.

  • Dietary protein: an essential nutrient for bone health.* Bonjour JP.

Service of Bone Diseases, University Hospital, Rue Micheli-Du-Crest, 1211 Geneva, Switzerland.

Nutrition plays a major role in the development and maintenance of bone structures resistant to usual mechanical loadings. In addition to calcium in the presence of an adequate vitamin D supply, proteins represent a key nutrient for bone health, and thereby in the prevention of osteoporosis. In sharp opposition to experimental and clinical evidence, it has been alleged that proteins, particularly those from animal sources, might be deleterious for bone health by inducing chronic metabolic acidosis which in turn would be responsible for increased calciuria and accelerated mineral dissolution. This claim is based on an hypothesis that artificially assembles various notions, including in vitro observations on the physical-chemical property of apatite crystal, short term human studies on the calciuric response to increased protein intakes, as well as retrospective inter-ethnic comparisons on the prevalence of hip fractures. The main purpose of this review is to analyze the evidence that refutes a relation of causality between the elements of this putative patho-physiological "cascade" that purports that animal proteins are causally associated with an increased incidence of osteoporotic fractures. In contrast, many experimental and clinical published data concur to indicate that low protein intake negatively affects bone health. Thus, selective deficiency in dietary proteins causes marked deterioration in bone mass, micro architecture and strength, the hallmark of osteoporosis. In the elderly, low protein intakes are often observed in patients with hip fracture. In these patients intervention study after orthopedic management demonstrates that protein supplementation as given in the form of casein, attenuates post-fracture bone loss, increases muscles strength, reduces medical complications and hospital stay. In agreement with both experimental and clinical intervention studies, large prospective epidemiologic observations indicate that relatively high protein intakes, including those from animal sources are associated with increased bone mineral mass and reduced incidence of osteoporotic fractures. As to the increased calciuria that can be observed in response to an augmentation in either animal or vegetal proteins it can be explained by a stimulation of the intestinal calcium absorption. Dietary proteins also enhance IGF-1, a factor that exerts positive activity on skeletal development and bone formation. Consequently, dietary proteins are as essential as calcium and vitamin D for bone health and osteoporosis prevention. Furthermore, there is no consistent evidence for superiority of vegetal over animal proteins on calcium metabolism, bone loss prevention and risk reduction of fragility fractures.

Osteoporos Int. 2006;17(9):1398-403.

  • The effect of a low-carbohydrate diet on bone turnover.* Carter JD, Vasey FB, Valeriano J.

Department of Internal Medicine, Division of Rheumatology, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 81, Tampa, Florida 33612, USA.

INTRODUCTION: Low-carbohydrate diets have become popular as weight loss techniques. These diets are high in protein, saturated fats, and omega-6 fatty acids. They also lead to a ketogenic state. These factors could lead to increased bone turnover. This study was designed to see whether a low-carbohydrate diet would lead to increased bone turnover in humans. METHODS: Thirty patients (15 study subjects and 15 controls) were recruited for this 3-month study. The 15 patients on the diet were instructed to consume less than 20 g of carbohydrates per day for the 1st month and then less than 40 g per day for months 2 and 3. Control subjects had no restrictions on their diet. The primary end point was urinary N-telopeptide (UNTx) at 3 months. Secondary end points included UNTx at 1 month, bone-specific alkaline phosphatase (BSAP) at 1 month, bone turnover ratio (BSAP/UNTx) at 1 month, and weight loss. RESULTS: The mean UNTx in the study subjects increased by 1.6 [95% confidence interval (CI) +/-22.8] compared with an increase of 1.9 (95% CI +/-17.6) in the controls at 3 months (p=0.86). The mean UNTx decreased by 2.2 (95% CI +/-27.2) and 3.1 (95% CI +/-17.6) at 1 month in the dieters and controls, respectively (p=0.36). The mean BSAP decreased by 0.53 (95% CI +/-2.96) in the dieters and increased by 0.34 (95% CI +/-2.92) in the controls at 1 month (p=0.27). The bone turnover ratio increased by 0.08 (95% CI +/-0.81) in the dieters and by 0.05 (95% CI +/- 0.27) in the controls at 1 month (p=0.78). The dieters lost 6.39 kg versus 1.05 kg for the controls at 3 months (p=0.0008). CONCLUSIONS: Although the patients on the low-carbohydrate diet did lose significantly more weight than the controls did, the diet did not increase bone turnover markers compared with controls at any time point. Further, there was no significant change in the bone turnover ratio compared with controls.