September 30, 2012

Nutritional Biochemistry

What I actually eat, part II – “IFIK” (circa Q3 2012)

Read Time 8 minutes

Note to readers: This post was written in September of 2012.  PLEASE do not ask me why I eat ‘this’ or why I don’t eat ‘that’ — as what is shown here does not necessarily reflect what or how I eat today (or more importantly, how you should eat).  My diet evolves constantly, due to my constant tweaking and self-experimentation. Over time, I’ll share it here and there, but what I eat is not at all the focus of this blog.  I ask that you refrains for asking questions about what I eat your comments.


For reasons I don’t fully understand the most read post on this blog is one I wrote very quickly and with very little thought.  I wrote it in response to a question I’m asked all the time, “What do you actually eat?”  The post, aptly titled, What I actually eat, has more than twice the traffic of the next three most read posts combined. Go figure.

After a full year in “strict” (i.e., no “cheat” days) nutritional ketosis I wanted to experiment with other eating patterns.  I had been reading about intermittent fasting (IF), and had a few discussions and exchanges with Mark Sisson and Robb Wolf about it.  Though I don’t know Brad Pilon or Martin Berkhan personally, I’d also read a few interesting things they had written.

Why the change?

My curiosity was sufficiently piqued to break a golden rule – if it ain’t broke, don’t fix it.

I was very happy after a year of nutritional ketosis, but I did wonder if I could improve on a few things.  For starters, as my cycling season was about to ramp up, I wondered what it would be like to weigh 75 kg (165 pounds) instead of my steady-state weight of about 78 kg (172 pounds).  I know 3 kg does not sound like a lot, but it can make a huge difference when riding up Mount Palomar, assuming one can preserve power output. I also liked the idea of not spending so much time eating.  As you probably know, I’m pretty obsessive about how I utilize the 168 hours in each week and resent anything that takes me away from my family, my work, and my training.  (This includes sleep, which I wish I could figure out a way to thrive without.)

In the end, I think Mark Sisson finally just egged me on enough to agree to at least give it try – even just one day per week.  And with that, I embarked on the next phase of my nutritional odyssey.

I decided, in early May, to start with the following protocol: one meal per 24 hours, twice a week.  On the other 5 days I consumed my usual keto-diet.  On the two IF days I would just eat one meal at around dinner time.  I still consumed normal amounts of liquids (water, coffee, tea) and supplements (see list below), with one exception – on fasting days I doubled the amount of sodium I supplemented via bouillon from 2 gm per day to 4 gm per day.

Like all nutritional changes, this one took some getting used to.  Because I exercise in the mornings, on fasting days I would get pretty hungry by about 10 or 11 am.  Interestingly, though, by about 2 pm, as my blood glucose levels would be between 60 and 70 mg/dL, I would start to feel completely fine.  In fact, by about 5 or 6 pm, just before eating my meal, I found I wasn’t really hungry.  This may have been due to the fact that my B-OHB levels were usually above 3 mM by this time of day.

Why do I call it “IFIK?”

Not surprisingly, after eating 100 gm of protein and 40 gm of carbohydrates in one sitting, my B-OHB levels would fall, often below 0.5 mM, the practical threshold of nutritional ketosis.  Usually within 24 hours I’d be back to my normal levels, generally between about 1 and 2 mM. But, the cycling in and out of ketosis was new to me, hence the phrase “intermittent fasting, intermittent ketosis,” or “IFIK.”  I guess you can see why I didn’t end up in marketing – “if-ik” doesn’t really have a nice ring to it.

The purpose of this post is not to provide a detailed overview of IF or ketosis, but rather to address the following common questions I often get asked in response to the original post on what I ate:

  1. Question: Peter, why do you eat so much dairy?  Answer: I don’t.  That was a year ago.  I did eat a lot of dairy, and seemed to tolerate it quite well. I realize that’s not true for everyone. Regardless, I seem to eat much less today.
  2. Question: Peter, is ketosis for everyone? Answer: Of course not.  Besides oxygen and water, few things are.
  3. Question: Peter, why do you eat so much meat? Answer: I don’t.  In fact, some days I don’t eat any.  Other days I do. I obviously don’t think there is anything harmful with eating meat (read this post for a refresher), but I’m quite happy eating lots of non-meat items, too.
  4. Question: Peter, how can anyone possibly do anything athletic without carb loading? Answer: It’s easy.  Anyone can do it, if they are just patient and let their body adapt.
  5. Question: Peter, you eat like a freak (ok, not really a question!) Response: And your point is?

What happened after several months of IFIK?

Interestingly, I did lose weight.  After briefly hitting 163 to 164 pounds, I settled out at where I am right now, about 165 to 166 pounds, right at my 75 kg target.  I have not yet repeated a DEXA scan to confirm, but I suspect I lost a bit of muscle, along with more fat, probably at about a 1:2 ratio.  My last DEXA measured a body fat of about 9%, and I suspect I’m about the same, though my waist is half an inch smaller than when I started, so I may be closer to 8%.

Why do I think this happened?

In the IF community there are really two (maybe more) theories on why I lost weight.  I won’t describe them here in any detail, but will do so in subsequent posts.  One hypothesis is that I’m simply consuming fewer of the same high quality calories than I did before.  The other hypothesis is that the physiologic response to IF (rather than the response to prolonged fasting) is to increase my REE during the period of IF, possibly through the up- and or down-regulation of various hormones.  Of course, it could be a combination of these, or something entirely different, too.


Before getting to the part that folks who are still reading probably care about, let me point out a few differences between what I eat today and what I ate a year ago.

  1. I consume, on average, fewer calories per day.  I am also lighter, and we know TEE varies with body mass, so it’s not surprising that most days I am not eating over 4,000 kcal, as I used to. Of course, one might argue my body has become more metabolically efficient at utilizing substrate, and so my REE is lower than it was a year ago.  Finally, I do exercise less than last year.  Hence, there are many explanations for this difference.
  2. I consume less dairy. Don’t read too much into this.  There is nothing deliberate about it, just an observation of my behavior.
  3. I consume less meat of all varieties.  Again, don’t read too much into this.  I have no explanation except that I seem to crave it in lower amounts and less frequently.
  4. I consume more overall carbohydrates, though still virtually zero sugar or refined carbohydrates. Most of this additional carbohydrate is in the form of nuts and SuperStarch.
  5. I consume virtually zero sugar substitutes, except for the little bit in my SuperStarch and protein powder (sucralose).  I also drink, at most, about one diet soda per month.
  6. I spend less money on food.
  7. I spend less time eating.
  8. Currently I only eat three meals per day about once a week. I eat two meals per day probably 4 times per week, and one meal per day twice per week.

To calculate the nutritional content of my intake I use a piece of software called Nutritionist Pro, which is not for the faint of heart. It’s one step removed from a DOS prompt. In addition to costing about $600 a year, it’s not exactly user-friendly.  I’d probably describe it as “user-hostile,” actually.  But, it’s really accurate and has a database that is unrivaled.  The reports, once you learn how to generate them, are very good, also.

Three consecutive days of representative eating

Keep in mind, I don’t count my calories or weigh my food normally.  I do it periodically, such as at this time, when I’m curious as to what I’m actually eating.  I believe I’m able to do so without eliciting the Hawthorne Effect, but obviously one can never be positive.


  • 7 am — morning workout – flat intervals on bike (75 minutes).
  • 1 pm – Nicoise salad:2 cup butterhead lettuce, 1 tomato, 10 black olives, 8 oz tuna steak, 1 hard boiled egg, 0.5 cup red onion, 2 oz lemon juice, 4 tbsp olive oil, 1 tbsp mustard.
  • 7 pm – Chicken salad with nuts:2 cup romaine lettuce, 1 tomato, 0.5 cup cucumber, 2 oz cashews, 2 oz walnuts, 8 oz chicken breast, 6 tbsp olive oil, 2 tbsp balsamic vinegar.

Daily totals:

Carbohydrate – 89 gm

Protein – 131 gm

Fat – 218 gm (about 15% SFA, 70% MUFA, 15% PUFA)

Calories – 2,900


  • 6 am — morning workout – high intensity dry land (90 minutes).
  • 3 pm – The “Peter Kaufman shake” (named after my good friend, Peter Kaufman at Generation UCAN, who hooked me up with the recipe):
    4 oz heavy cream, 8 oz zero-sugar almond milk, 1 pack chocolate protein SuperStarch, 2 tablespoons almond butter, 8 gm additional glutamine, 1 tray of ice cubes (blended to smoothie consistency).
  • 7 pm – Chicken-nut omelet:
    4 eggs, 0.5 avocado, 3.5 oz cheddar, 3 oz red onion, 2 oz walnuts, 2 oz cashews, 4.5 oz chicken thigh, 2 tbsp butter

Daily totals:

Carbohydrate – 60 gm (30 gm of which is SuperStarch)

Protein – 151 gm

Fat – 226 gm (about 40% SFA, 35% MUFA, 25% PUFA)

Calories – 2,800


  • 7 am — morning workout – hill intervals on bike (75 minutes).
  • 5 pm – Attia super salad:
    1.5 cup romaine lettuce, 0.5 cup cucumber, 0.25 cup mushroom, 1 tomato, 3 oz sliced T-bone steak, 2 oz cashews, 2 oz peanuts, 2 oz macadamia nuts, 8 tbsp olive oil, 2 tbsp balsamic vinegar.
  • Between 6 and 8 pm – after-dinner snack consisting of:
    3 oz cashews, 1 oz almonds, 2 oz peanuts, 1 oz macadamia nuts, 2 cups of coffee with a total of 6 tbsp heavy cream.

Daily totals:

Carbohydrate – 94 gm

Protein – 93 gm

Fat – 369 gm (about 20% SFA, 65% MUFA, 15% PUFA)

Calories – 3,800

My daily supplements

Note: I am only listing the products I use, and not trying to convince you that my brand of vitamin D is superior to another.  If I feel strongly about a product, I note it. But this is not a product pitch. I don’t make one penny off you buying any of these products.

Fish oil

1 tablespoon of Carlson’s Very Finest Fish Oil, providing 2,400 mg EPA and 1,500 mg DHA.  I do feel this is a superior product and I’ve had detailed toxicology analytics conducted on the product to confirm the absence of lead, arsenic, mercury, and other toxins.

Vitamin D

5,000 IU D3 in gel capsule, by NOW.


400 mg magnesium oxide by Nature Made.


2,000 mg in the form of bouillon, typically by Knorr.

MCT oil

Either 2 or 3 tablespoons, depending on activity level, by NOW.


2 capsules of Mark Sisson’s Primal Flora, providing 60 billion CFU.  The reason I use Mark’s product is because I know and trust him, and I know how much homework he did in formulating this product.

One of the topics I’m currently getting steeped in is gut biota, and I’m hanging out a lot with a San Diego expert on the topic, UCSD Professor Larry Smarr, who has repeatedly sequenced his entire gut biome, with the help of Craig Venter at Synthetic Genomics and others at MIT.  As Larry points out, the challenge of “moving the needle” with probiotics is that they only provide the aerobic bacteria while, of course, most of our gut biome is anaerobic.  Stay tuned for much more on this topic.

Closing thoughts

  1. My performance, especially in light of my reduced training volume (or maybe because of it!) has not deteriorated.  In fact, this week I had 3 best times in 3 of the activities I do weekly (tire flipping/sledge hammer/plyometic routine (1:04); short sprint up 15-18% grade (0:39), and long sprint up 8% grade (3:29)).  It’s possible the added carbohydrate, relative to my constantly ketotic state, has facilitated this, despite consuming about 15% of the carbohydrate I used to consume on my “standard American diet” circa 2008.
  2. I will discuss the impact on my biomarkers in a separate post.
  3. The only drawback I’ve noticed of IFIK so far is that I’ve inadvertently turned my daughter off nuts.  About 4 months ago, after having three consecutive identical dinners (chicken-nut-salad), she called my wife into her room as she woke up and said, “Mommy…we need to talk.  We need to have something different for dinner tonight.  We can have steak…we can have sausage…we can even have regular salad without nuts…but I can’t have nuts in my salad anymore!”  Poor girl… So now I have to make my salads separately.


Photo by Dan Gold on Unsplash

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  1. Hi Peter,

    I’ve been on a low carb diet for about 6 months and although I have lost weight 9about 10 lbs), I fully expected my body composition to have changed more drastically. I have plateaued and can’t figure out why. Is there a protocol you could suggest that could help me figure this out? For example, should I eliminate dairy (even if I tolerate it well) to see if this will help me break through this plateau? It could be my protein intake or perhaps my caloric intake is too high given my level of physical activity. I hate the idea of counting calories but the one macro nutrient I try to keep close tabs on is my carb intake and I am positive I’m never more than 100g per day and usually more like 50 – 75 (almost all from veggies, small amounts of fruits or nuts). I’m frustrated because a year ago, pasta, cookies, white bread, french fries and ice cream were all staples in my diet so I feel any change from here will be minor.


  2. hi Peter,
    I really appreciate your generosity in sharing your knowledge (and on going experiments) on nutrition and its consequences for human health. I did not find anything on A2 beta-casein and its variant on the blog, and I would be very interested in knowing about the last research on the subject, if you ever cared to check those studies pointing to its relevance in several deseases (cancer, CVD, etc). At any rate, thank you and good work,

  3. Hi Peter,

    What is your opinion of supplementing with coconut oil for brain health (on a low-carb diet)? Dr. Lipid and Robb Wolf had an exchange about it on twitter. Would you consider it a safe, healthy, benificial fat? Someone in their conversation called it very dangerous for cardiovascular health. Thank you very much, Maryann

  4. Hi Peter,

    I read your personal HOMA IR test results dated September 2009 and May 2011 and notice that your fasting BG is 97 and then drops to 83 post prandial ! where as your fasting BG in 2009 was lower at 93 when you were Insulin Resistant.
    Why does this happen ? I am facing a similar situation on a carb restricted diet: while my lipids have improved (HDL up from 40 to 59, TG down from 120 to 68, TC down from 225 to 180, LDL down from 147 to 118, weight down from 160 pounds to 140 pounds ) my FBG has increased 90 to 100. My BMI is 20.
    100 is considered predibetic in India – I am confused.

    • Fasting glucose is a very misleading indication of IR. In fact, HOMA-IR is barely better. Fasting insulin is better than both, but OGTT is much better.

  5. Hi Peter,
    Great job with this blog. I have been following a low carb diet for some time which means I eat a higher than average amount of protein. I would value you opinion on this recent article (see link) that equates higher protein intake with increased rates of all-cause mortality (twice the rate) and also death from cancer and diabetes (four times the rate) compared with low protein consumption. This is applicable to those between 50-65 years of age (I am 53) who have >20% of calories daily from protein. Admittedly this is a population based study with all the flaws inherent in this design, but it is ‘food for thought’. Thanks

  6. Peter,

    Awesome ! I was hoping you’d say something like that. I’ll give the study as much credence as you have (none!).

    Again, thanks for all your insight and advice to us LC/HF followers.

  7. “”Bill, please tell you didn’t just ask me about a study on the lifespan of mice and ask me to comment, right?””

    Haha! Where’s the LIKE button?!

    • Hahaah! That article is a report on a report, and gives no pertinent specific information at all. Excess sugar/carbs is now well-known to be the primary cause of NAFLD, and metabolic syndrome in humans. Mice live up to 150 days? That study is very bad science! A very old but famous Harvard study with rats found that when fed a starvation diet from birth to adulthood, while not growing as large, they lived twice as long, not getting as sick throughout their lives as those that were fed the normal rat diet! So much for rodents!

  8. No question, just a “Thank you very much.” I’m 70 years old, have a 3-yr old son and young wife, play tennis 3-5 times/week, and have been following a low carb, totally no sugar regimen via Mark Sisson et. al., for a while. My weight vacillates around 175 pounds, but I know I’ll feel much better at 165. While advice from the gurus is great, there’s nothing like a true life account backed by scientific data to bolster my new belief system and diet! The advanced blood tests in America are not available here, in The Philippines. So, I take no tests, except blood pressure that is constant at 110/70. As you all know, changing to high saturated fat, and eating pork and red meat after almost a lifetime of low fat with only chicken, fish, and seafood can be scary, especially when one has had a coronary heart attack, as I have, at 63 years of age. At 6’1” I was 162 pounds running track at age 17. Before my heart attack I had struggled to maintain a weight around 200 lbs, and was a whopping 215 lbs at my heart attack. Like you, I didn’t know how I’d gained so much weight. Looking back, I’d stopped exercising as much and was addicted to ice cream, and was probably somewhat depressed. But I always ate huge salads smothered in EEVO, that I also fried in, and thought I was following a healthy path! Now I only cook with coconut oil. Recently I had begun to question the amount of animal fat I was ingesting, of course with regard to my arterial health and heart attack resistance! It’s always on my mind, and can lead to depression. [Note: Robin Williams was overweight for quite a while, and had open heart surgery not too long before his suicide.] After reading your blog, I am no longer concerned about my arteries as related to high saturated fat intake. I love eating this way. Heavy cream (in coffee and fruit salad deserts), cream cheese, and butter, bacon (slow cooked) and eggs are so satisfying! It seems so much more natural, and is definitely more satiating than low fat consumption! I’m now considering lowering my protein intake. Few people follow an exercise regimen such as yours, so I agree with your recommendation to not eat as you do, among other reasons. But examples of what you eat will always be highly illustrative and educational for your followers. You should understand this as it relates to the traffic you get on your “what you eat” pages. Lastly, I’d just like to note that balsamic vinegar has sugar in it, and apple cider vinegar supports gut flora as opposed to white distilled vinegar that destroys gut flora. BTW – a great way to add resistant starch to your diet is cold potato salad! Thank you again! Comments are always appreciated.

  9. Hey Peter, just wondering if you are doing a post workout protein shake on days you bike and/or on days you do your dry land workouts? You said you don’t eat breakfast but was just wondering if you did any post workout nutrition that would break your IF until lunch or if you just use protein from the two meals you do consume for recovery? Thanks.

  10. Hi Peter, Happy New Year *2015* to you and your family; I hope all is/are well! In this post on “IFIK” you wrote:

    One of the topics I’m currently getting steeped in is gut biota, and I’m hanging out a lot with a San Diego expert on the topic, UCSD Professor Larry Smarr, who has repeatedly sequenced his entire gut biome, with the help of Craig Venter at Synthetic Genomics and others at MIT. As Larry points out, the challenge of “moving the needle” with probiotics is that they only provide the aerobic bacteria while, of course, most of our gut biome is anaerobic. Stay tuned for much more on this topic.

    Any updates on this topic you might share at this time are most appreciated! Are you still taking Primal Flora 2/day? Thank you with my Regards, KM

  11. OK I just discovered your blog last night – because I’m being told I am pre-diabetic and am try to wrap my brain around what that means. Second impression – fueled by a deep skepticism for anyone who eats loads of saturated fats is this: when you say “The post, aptly titled, What I actually eat, has more than twice the traffic of the next three most read posts combined. Go figure.” Might that be due to the blog being titled “The Eating Academy”?

    First impression was that what I’ve read so far is intriguing and rings of veracity. I am Anxious to get my blood sugar levels down and stable so I’m going to read on…


    • Dr Tim Noakes got into trouble for answering this, you know that of course.

  12. Is there bad fats in keto? Such as regular butter or consuming high amount of grain fed meat fat? Or probably gulping on canola oil? Also, im concerned about the Knorr part, isnt consuming large amount of MSG detrimental to our health? Thank you in advance for answering my question 🙂

  13. Hello Dr Attia,

    Today I decided to take the switch to a keto diet, and have been inspired by your presentations and also from Dr Malhotra. I take it you follow a mediterranean based ketogenic diet? Can I ask how long do you think it will take for my spare tyre(s) to disappear? Many thanks.

  14. Hi Dr. Attia,

    What you provide for the general public as far as free nutritional information is phenomenal & commendable. I have been in nutritional ketosis for the past 3 years, and have been intermittently fasting for 16 hours per day for the last 4 years. These two methods have worked synergistically to eliminate my autoimmune issues like eczema; have decreased my bf to 6.10%; and my crp is below 1.0. I enjoy living this way, but how sustainable is this? I’m 23 & worried my hormones may tank in my 30s.

    Best wishes,
    Kwadwo A. Boateng

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