Digging into the Bodyrecomposition Mailbag

Since I can’t think of any actual topic this week and think I can answer these questions in a fairly brief manner, I’m just going to clear out some of my questions.  Topics will include women and DEXA, oddities about pregnancy metabolism, endurance nutrition and a bit about health habits when you have bipolar.

Question: Hi Lyle, I recently did a DEXA scan to get an estimate of my body fat % – I’m female, 28 years old, weight train regularly. My DEXA scan results: 5’3, weighing 59kg and an ‘average’ of 20% body fat. I say ‘average’ as the scan showed that the body fat % in my upper body (arms, torso) was 14% while my lower body (hips, thighs) was 27%. Is it fair for me to take the average of these and consider myself to be 20% body fat?

Answer: The above type of question is becoming more and more frequent as more people are using DEXA scans to get an estimate of bodyfat percentage (BF%).   Because of the way DEXA works, it will churn out different BF% for the upper and lower body and this can be confusing.  First and foremost, the above is a completely normal female body fat patterning as women generally carry more body fat in the lower body than upper body (a male would typically have the opposite pattern).  I say generally as there can be exceptions where women have either a very even body fat pattern or more of a male-like upper body fat patterning; the latter typically occurs in situations were testosterone is above normal.  So far as the main question, should the values be averaged to get a usable BF%? The answer is yes.  In any of my books and most discussions of applications of BF%, it’s whole-body BF% that is relevant, not the individual distributions.

Question: I was wondering if you could make sense of this article in terms of what you know about human metabolism:

Answer: The paper in question deals with the issue of resting metabolic rate (RMR) and it’s determinants.  Normally, the largest determinant of RMR is lean body mass (LBM).  Here I’m talking about all LBM, not just muscle.  Organs, brain, etc. actually burn far more calories per day than muscle and LBM predicts a majority (off the top of my head: 75% or so) of RMR.  But this study found that in pregnant women, it was the amount of body fat that predicted RMR, concluding that:

It is proposed that pregnancy represents a unique condition during which BMR is regulated by maternal adipose reserves. An augmented BMR in overweight pregnant women may be protective, given that excessive weight gain may be detrimental to neonatal and maternal health.

First and foremost, realize that in the age of leptin, we know that a great deal of metabolism is regulated by body fat stores.  Quite in fact, as body fat drops, it is the loss of body fat that contributes significantly to the drop in resting energy expenditure.  This isn’t due to the actual calorie burn of fat cells (which is quite low) but rather due to what’s happening hormonally (primarily the drop in leptin).

In any case, first let me state that pregnancy is neither my area of interest nor expertise.  I touch only on it like twice in the forthcoming women’s book and can only comment so much here.  But a lot changes in pregnancy and the basic fact is that at least part of why women store more fat than men (and specifically in the lower body) is due to the crucial importance of body fat during pregnancy and breastfeeding.  Fat is used preferentially towards the end of pregnancy for fuel and fuels breastfeeding; quite in fact the normally difficult mobilization of lower body fat reverses itself with that fat becoming easier to mobilize (years ago I played with the idea of trying to mimick the hormonal situation of breastfeeding to cause this but the project went nowhere).

But this means that it makes a certain logical sense that women’s metabolisms would be controlled by body fat in this one situation; this would be to ensure that sufficient calories are available for the baby instead of being burned off for other reasons.  I’m not entirely sure what their conclusion is getting at but overall it’s just saying that there is a change in metabolism during pregnancy where body fat becomes the regulator of RMR.

Question: Good Afternoon, I have been reading your site for a while and have put lots of it to good uses but one thing I cant find and its my area of struggle. Fueling my post work afternoon (3pm) workouts. I am a competitive cyclist and often 2 week day hard workouts as soon as i get home from work. I will eat a small lunch then 1-1.5 hrs after it I will eat what more resembles a lunch about 500-600 cals which puts me 2 hrs out from my intense workout. But I often need to take on addition cals during ride to finish it with success otherwise it gets ugly. Any suggestions? thanks!

Answer: An enormous amount of research has looked at the issue of endurance nutrition both in terms of fluid and nutrient intake (this is all discussed ad nauseum in The Protein Book).  In basic summary, a fluid intake of roughly 32 oz per hour (a large water bottle is typically 28 oz or so) with 30-60 grams of carbohydrate (from some type of glucose solution generally) and *maybe* 8-10 grams of a rapidly digestible protein (think whey) is considered optimal.  Cool fluids seem to be absorbed most quickly and the tiny bit of sodium/potassium is, contrary to belief, mainly there for taste reasons.

A little bit more carbohydrate (up to like 70 grams per hour) can be used if a mixture of carbs (i.e. glucose and some fructose) is used and the whey protein *may* help to limit muscle damage and *might* help with performance (this is debatable).  For easier or shorter rides, 30 grams of carbs per hour and less total fluid is usually fine and for harder workouts, 60 grams per hour in the full fluid would be appropriate.  It’s important to use enough fluid if you use the maximum carbs since extremely concentrated solutions (above around 7% or thereabouts) aren’t absorbed as well.

Note: women can get by with about half the amounts of both fluid and carbohydrate that would be typical for males for various reasons).

Drinking about 1/4 of the bottle (~8 fluid) every 15 minutes or so will provide sufficient fluid and nutrients to fuel the ride.  If you’re going into the ride particularly underfed, you can start the ride with a drink, or wait until you’re in your warmups.  Some people can get a drop in blood sugar (it’s more rare than you’d think) but exercise blunts the insulin response to carbs.

Question: Hi Lyle I am also Bipolar II (discovered and diagnosed by chance about four years ago) and find a lot of what you wrote on the subject this past year very familiar. I’m wondering, however, if you have a specific diet and exercise routine you would suggest for bipolar people? I’d like to add that I’m also ADHD so I prefer to keep carbs as low as possible as it tends to clear my mind, I’m just not sure if that is optimum given my overall mental condition.

Answer: Ok, this is a question I thought long and hard about answering although I’ve addressed what I personally do to some degree in my various updates.   I’m going to address it in a sort of roundabout fashion by only describing what I personally do or was recommended by my Nurse Practitioner.  I’m taking this approach since this is an issue of mental illness, I’m not a qualified professional on the topic and, to date, I’ve only looked into it very superficially and the potential ramifications of anything that goes wrong can be enormous. So, just as I would at a DBSA support meeting, I will talk only from my own experience with no recommendations being made or implied.

When I was first diagnosed, the basic gist of what my NP and psychiatrist recommended was:

  1. Ensuring a solid sleep schedule (too little sleep can induce hypomania).  I go to sleep every night by 11pm and wake up at 8:30 to feed and potty my dogs and the number of times I haven’t done this in the last year I can count on less than one hand.
  2. Regular exercise.  They recommended 7 times per week and when I asked why, they said that if they recommend 7, people might do 5 but if they recommend 5 people will do 3.  This is true.  While they skirted on details, regular exercise helps to, as my NP put it “Eliminate crud in the brain.” That’s as technical as I’ve gotten on the topic.  I personally am currently doing 4 days/week in the weight room and my only cardio is walking the dogs because indoor cardio sucks.  If there is a difference in type of exercise here, I’m not aware of it because I’ve never bothered to look.  I would generally imagine that a combination of weights and cardio is ideal.
  3. A diet including plenty of fruits and vegetables.  Common sense but who knows what all nutrients, etc. play a role in all of this.  I’m not great with vegetables since they bore me but I generally get at least one serving with 3-4 pieces of fruit per day.
  4. Regular Vitamin D intake. They recommended 2k IU, I take 5k IU just because.
  5. Regular fish oil intake.  They recommended 2 grams of preformed fish oils (which would contain 600 mg of combined EPA/DHA generally) but I’ve taken 3 times that much forever (a dose of combined EPA/DHA of 1.8-3.0 grams per day is what I recommend in my books).  There is some limited data that this helps with a variety of mental illnesses although it’s mixed.

That’s really it (I take a basic multivitamin just because and use zinc and magnesium at bedtime to ensure good sleep) and most of what they recommended was stuff I was doing already.  They commented that part of why I may have avoided a complete hypomanic meltdown (as happened in late 2014) was due to my already existing habits.  I was already doing most of the things I should have been.

I should note, since I get asked about it all the time, that there is some *very limited* evidence that ketogenic diets help to control bipolar.  I actually find this interesting as the ketogenic diet was used clinically to control epilepsy and a lot of bipolar drugs started life as epilepsy treatment drugs.  This suggests some type of shared mechanism between the two.  I also find it ironic on top of that given that my first book was on ketogenic diets.  Beyond that, I haven’t yet had time to look into the topic in any detail.

However, I am not currently following one because I like carbohydrates and know that I wouldn’t follow one indefinitely.  It also wouldn’t support my weight training so I just stick with a moderate carb diet and take my lamictal (I’m also on Deplin since a genetic test showed that I don’t convert folate to methylfolate).  I’m sure someone will get up my ass about preferring a medication over a “natural” approach but, here’s the thing: good advice not followed is bad advice.  I know I won’t do a long-term keto diet and my med dose is very low with no sides.  So I take low-dose meds over a diet I know I won’t do.  If I were in a situation where the meds weren’t controlling my mood or the side effects were intractable, I’d consider sucking it up and doing keto.  Since neither of those are the case….

But the above is what I do which seems to be consistent with the research and is what my NP told me to do.  I won’t say more than that.   I’m in no way recommending what I do as what should be done and am simply reporting it from my personal experience.

That’s all folks.

 

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