Macros, ketones, and carbs. Oh, my!

It is pretty well established, in my professional opinion (i.e., the scientific literature), that the primary factor in body weight management is caloric balance.  I have shared several times that this can be estimated to account for about half of our weight management efforts.  It is established that there are but three diets—eucaloric (in which body weight is maintained; calories in = calories out), hypercaloric (weight is being gained; calories in > calories out), and hypocaloric (weight is being lost; calories in < calories out).  In other words, to lose weight one must be on a hypocaloric diet.  Eat less and one will lose weight—thus, if you are trying to lose weight and not, you may not be consuming the calories (or expending the calories) you think you are.

Now, there may be circumstances where caloric balance is adversely affected (e.g., one is eating too few calories or has been hypocaloric for too long—metabolism has slowed), but as a rule a modest reduction in caloric balance (3500-7000 kcal per week) will lead to a sustainable fat loss (our goal, after all, is to lose fat not muscle) over time.  Thus, I would like to put some focus on “macros”.  Dr. Mike Israetel (Temple University; Renaissance Periodization) estimates that macro balance accounts for about 30% of weight management.  What, then, is a macro?

Macros (or macronutrients) include the carbohydrates, fats, and proteins in the diet.  There is no consensus on what is the ideal macro balance.  This is mostly attributable to the fact that caloric balance plays a bigger role and the science is not very uniform in how this is controlled in the many studies.  It is also ascribed to the fact that everyone is different and will, thus, respond differently to the variety of diets.  So, how can one know which macro approach is best—for them?  In my experience, trial and error.

Selecting the appropriate macro balance will depend on one’s goals and exercise habits.  With these in mind, it is a bit easier to sort through all the confusion and diet hype.  While there are many names for diets in popular use (e.g., “ketogenic”, “Paleo”, “Wild Diet”, “Adkin’s”, “Weight Watchers”, “Mediterranean Diet”, etc.), they all ascribe some degree of macro balance—whether explicit or implicit—as well as addressing caloric balance.  Thus, I prefer to just look at the numbers.

If caloric balance is most important, why even bother with counting macros?  Honestly, if you are sedentary and significantly over-weight, it is probably not going to make much difference (Dr. Mark Haub, Kansas State University, lost 27 lb in 10 weeks on the “Twinkie Diet”).  If you are concerned, however, about performance, it will matter.

When it comes to macro balance, it is best to first address protein.  Protein is, perhaps, the most stable of the macro needs.  There is some greater need for athletes—or nonathletes who exercise intensely and for prolonged durations.  Protein accounts for roughly 5-15% of one’s energy needs (i.e., rather little protein is used to make adenosine triphosphate or ATP for muscular contraction).  The body prefers to reserve protein for tissue structure, enzymes, etc.

The Dietary Reference Intake (DRI) for protein is 0.8 g per kg of body weight (0.36 g per pound).  Note, these values are the minimum necessary to prevent a deficiency.  A common recommendation for the average individual is around 0.6 g per pound.  If one is active—and particularly if one is trying to build muscles—the recommendations go up.  How much higher is cause for debate.  The high end is probably not near as high as bodybuilders might consume, e.g., >2 g/lb (but, since bodybuilders need to be hypercaloric to build muscle, it doesn’t matter much for them).  The low end (0.6-0.8 g per pound) is probably sufficient for the regular exerciser.  For most intense exercisers, 1.0 g per pound seems to be a reasonable target.  Thus, I recommend (once the total daily energy expenditure is established) setting 1.0 g/lb as the goal and determining the remaining macro balance—carbohydrates and fats—based on the remaining calories and personal needs and preference.

The options that remain are: 1) zero carbs, 2) low carbs, and 3) high carbs.  (Which, conversely, implies: 1) high fat, 2) low fat, and 3) zero fat. –Note that “zero” is not really “0”.  We have an essential need for some fat and carbs, and it is unlikely that anyone can totally eliminate either from the diet.)  Briefly, I would like to address the pros and cons of each diet.

Zero carbs.  This is your true “ketogenic diet”—less than 20-25 g of carbs.  Since protein in established at 1 g per pound of body weight, this means that nearly all of the remaining calories must come from “healthy” fats—ideally, avocados, olive oil, eggs, coconut oil, nuts, etc.

One of the biggest pros to a zero carb diet is that it will accelerate fat loss.  The body will rely on fat (stored, if the diet is hypocaloric) which results in the production of ketones.  There are medical benefits to ketosis—for some—but that is for another time.  And, if we are discussing weight management, we are actually talking about managing body fat stores.  Zero carbs is the fastest way to getting lean.

When it comes to performance, however, zero carbs will have a negative impact.  If one is over-fat and sedentary, this will make little difference.  If one is an endurance athlete, however, I am of the opinion that the jury is still out.  Many argue that it has no effect (some argue it has benefit) for endurance performance.  This may be true for long-distance endurance efforts where the body relies more heavily of fat metabolism for ATP production.  For the strength athlete and anyone looking to build muscle, I believe it safe to say that performance will be impaired.  High-intensity muscle contraction relies on the glycolytic (i.e., blood glucose and muscle glycogen) and the ATP-PC (stores of ATP and phosphocreatine in the muscle; more on this later) energy systems for the fuel to contract the muscle.  Since muscle hypertrophy and strength depend on overloading the muscle, anything that impairs the intensity of the workout and the volume of exercise performed will impact gains.

High carbs/low fats.  High carbs are best reserved for athletes involved in intense training.  For the average sedentary person, high carbs are likely to lead to greater fat deposition.  Carbs also have the lowest thermogenic effect of food than fats and proteins (proteins have the highest).  Thus, higher carbohydrate consumption has a more negative effect on fat burning.  For the athlete, high carbs are beneficial to performance.  Greater than 1.5 g per pound of body weight is recommended on intense training days.

Low carbs/high fats.  This approach seems to be the best approach for most who are seeking to gain muscle with minimal gain in fat—or optimally to lose fat while gaining or, at least, preserving muscle.  Here, 0.5-1.0 g carbs per pound is recommended, depending on training.  The benefit, here is that fat loss and performance is optimized.

I find, personally, that my performance tanks when I go below 50-60 g of carbs (<0.3 g/lb).  However, if I go much above 1.0 g/lb, my performance improves, but I lose the fight with body fat.  This is me, however, and everyone needs to find their own balance.  I do find that the higher fats are more satisfying and I am less inclined to be hungry and snack—thus, my total caloric intake is better controlled.

Remember, fat loss is most dependent upon being in a hypocaloric state.  Begin with determining what is your daily caloric need to maintain your weight.  Increase physical activity and cut your caloric intake to create a daily deficit of 500-1000 kcal per day (to lose 1-2 lb per week).  Then, determine what macro balance best fits your needs and preference.  Weight loss will likely be greater on a low carb diet owing to greater water loss (carbs tend to retain fluid), so do not be deceived into thinking that you are losing fat at a faster rate.  Use the mirror as your best indicator of body composition changes.

As, ultimately, muscle performance is dependent upon the availability of ATP, the goal should be to maximize stores for exercise.  It is recommended to plan carbohydrate consumption around training, if possible.  If, like me, training times don’t conform to optimal nutrient timing, reserve the greater carb consumption for the evening meal.  I also recommend supplementing with some form of creatine (creatine monohydrate or creatine HCl) to support the stores of ATP and the diet’s ability to restore ATP during exercise.  Creatine is perhaps the most well-documented supplement shown to have a positive effect on muscle performance and muscle performance.  As I, personally, experiment with reduced carbohydrates, I am finding that creatine doses pre- and post-exercise are increasing my performance and decreasing prolonged muscle soreness and cramping.  Currently, I am taking approximately 750 mg (1/8 tsp) of pure creatine HCl before and after each workout (according to the recommended dosage).  Micronized creatine monohydrate is fine but absorbs less effectively into the digestive tract and may require higher dosing and may cause greater gastric upset.  Research comparing the effectiveness of the different forms of creatine is yet limited.  Both seem to have the same overall effect and can offset some of the performance impairment caused by a low carb diet.

So, hopefully, some confusion over fats and carbs has been abated by this brief discussion.  The bottom line is that one should balance calories and macronutrients according to the individual needs.  Macro balance need not be so complicated.  Nor should macro balance be cause for heated debate.  Find what works best for you and stick with it.  Success requires effort—and the right effort.

Be your best today; be better tomorrow.

Carpe momento!

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