Category: Research Review

The topic of soy protein tends to bring up lots of argument and debate and certainly there is some good reason for this.   Depending on a huge number of factors, soy protein can be good, bad or neutral.  In general, the extreme stances are just that and the reality lies in the middle.  But the topic of today is not soy protein in general (discussed in detail in The Women’s Book Vol 1).  Rather, I want to examine if soy protein impacts thyroid function.

To examine the topic, I want to look at the following recent review:

Messina M, Redmond G. Effects of soy protein and soybean isoflavones on thyroid function in healthy adults and hypothyroid patients: a review of the relevant literature. Thyroid. (2006) 16:249-58.

A Primer on Thyroid Hormone Production

To give readers a brief background on the topic, the thyroid gland releases two primary hormones T4 and T3 (thyroxine and trio-iodothyronine respectively) in a ratio of roughly 80:20 in response to the signal sent by TSH (thyroid stimulating hormone). … Keep Reading

People who are serious about weight training tend to become quite detail oriented, fixating on every aspect of training.  In that regard, a common question is what the optimal rest interval between sets is. That is, how long should a trainee rest between sets of the same exercise to best achieve their goals.

There is actually no single answer to this question.  Rather, various factors go into determining what/if there is an optimal rest interval between sets to begin with.  To examine this issue, I want to look at a recent review paper on the topic:

Willardson, J.M. A brief review: Factors affecting the length of the rest interval between resistance exercise sets. J. Strength Cond. Res. 20(4):978-984. 2006

The Optimal Rest Interval is Context Specific

As I mentioned above, the optimal rest interval, which I will express here in either minutes or seconds, depends entirely on the context.  Primarily it depends on goal of the trainee in that this tends to define the type of weight training being done to begin with.… Keep Reading

Without fail, every decade seems to see the resurgence of the idea that extremely low-carbohydrate/ketogenic diets diets have a “metabolic advantage” over carb-based diets.  By that I mean that advocates claim that more weight/fat will be lost at the same (or even a higher) calorie level.  But is it true?

In examining the issue, I will be looking at the following paper:

Johnston CS et. al. Ketogenic low-carbohydrate diets have no metabolic advantage over nonketogenic low-carbohydrate diets. American Journal of Clinical Nutrition. (2006) 83: 1055-1061

A Disclaimer about Ketogenic Diets

Before I continue let me say that I have nothing against low-carbohydrate/ketogenic diets.  My first book The Ketogenic Diet was about nothing that topic although nowhere in that book did I specifically recommend them.   At the same time, at least some of my books have included low- or lowered carbohydrate phases in them.  Either those low-carbohydrate phases generate specifically biological effects (i.e.… Keep Reading

For a couple of decades, there has been an ongoing argument regarding the issue of “is a calorie a calorie” in terms of changes on body composition and other parameters.     In that vein is the idea that the body will respond drastically differently to the intake of “fast food” compared to similar meal from organic foods.

To examine this, I want to look at a recent paper titled:

Bray GA et. al. Hormonal Responses to a Fast-Food Meal Compared with Nutritionally Comparable Meals of Different Composition. Ann Nutr Metab. (2007) 51(2):163-71

Which actually made the comparison.  Let’s see what happened.

Yeah, a Calorie is Pretty Much a Calorie

Fundamentally, my belief is that, given identical macro-nutrient intakes (in terms of protein, carbs, and fats) that there is going to be little difference in terms of bodily response to a given meal.  There may be small differences mind you (and of course research supports that) but, overall, they are not large.… Keep Reading

This is sort of a departure from the typical paper I talk on this website as it deals with the history of beverages and how our body treats them physiologically.   While interesting in its own right (to me anyhow), it also provides some practical application that I’ll examine at the end of the article.

I think it’s especially relevant after the research review I posted on high fructose corn syrup for the simple fact that people are confounding what the real issue actually is in terms of causal effects on obesity.  As you’ll see as you read this, the issue isn’t with HFCS per se, but rather with the foods in which they are most commonly consumed: sweetened soft drinks.  But I’m getting ahead of myself.

Specifically I will be looking at the following paper”

Wolf A, Bray GA, Popkin BM. A short history of beverages and how our body
treats them.… Keep Reading