Friday, January 22, 2010

Weight Loss- The Problem with Calories

Calories in < Calories out= weight loss.
Calories in >Calories out= weight gain.

Is this the formula for weight loss? Sometimes... but not all the times. It's a simple equation and a mantra of fitness and diet enthusiasts everywhere. Many gyms have this proudly posted on their walls. You'll even read this on many diet focused websites. The problem with calories is that they are simply a unit of energy available in food. This perspective on food doesn't account for the message that food sends to your body. It assumes that all calories are created relatively equal.

Gary Taubes has a great book, Good Calories, Bad Calories, that thoughtfully explores our fascination with calories and the way it came about. A science journalist, Taubes has his share of critics as he blasts our conventional understanding of presumed nutritional gospel about cholesterol and calories.

Even my favorite reality television show, The Biggest Loser, regularly touts the simple mantra, "Calories in should be less than calories burned!" While I am routinely inspired by the contestants and impact of the show, that is one area where I will disagree.

Follow this reasoning.

1. Food initiates hormone responses. We know that insulin release is necessary for appropriate metabolism of foods. This is standard, textbook human physiology.

2. Insulin talks and interacts with other hormones... such as cortisol, testosterone, leptin, estrogen and more. This is an area that science continues to explores. Cutting edge clinicians are constantly amazed at the web-like interactions of different components of our body. The reality is that 1000 carbohydrate calories will cause a different insulin response than 1000 calories of fat or protein.

3. These hormones often take on a life of their own. For example, high insulin will promote insulin resistance over time. This promotes more cortisol release in an unusual stress response. Cortisol then promotes even more insulin resistance in a vicious cycle. As your body is now under a stress response, hormones like testosterone, estrogen and others can be shortchanged as the enzymes that produce them have altered activity.

Now let me ask you some questions;
a) What is the effect of high cortisol? It's bad.
b) What is the effect of low testosterone? It's bad.
c) What is the effect of altered estrogen metabolism? It's bad.
d) What is the effect of altered progesterone levels? It's bad.

...and the biggest question of them all...
e) What set this off to begin with? High insulin secondary to carbohydrate heavy meals... regardless of calorie content!

Let me make a point here. I am not a hard core low carb advocate. You must eat carbohydrates... the good ones. Your body loves carbs and they are designed to be utilized efficiently in the body. But I do think the Standard American Diet is carb heavy. Think about your meals and snacks. They are likely to be carbohydrates that promote an insulin surge.

The "calorie model" is useful to some degree.  But it is the foundation of "old school" nutrition and does not effectively consider the many other variables involved.


Monday, January 18, 2010

Your Epigenome

TIME magazine's cover story last week introduced the epigenome to the general public.  Biology's mantra has long been that your genes don't change.  Progressive doctors have been saying for years that while your genes don't change, the way your genes are expressed can be influenced.  This influence may even pass from parents to children. Your diet influences your genes!

Studies of altered epigenetic marking will be of profound importance for mechanistic understanding of the role of nutrition in health but especially for studies of the developmental origins of health.  Adv Exp Med Biol 2009;646:119-23. 

Another group of researchers goes on to write,
In the future, a better understanding of the mechanisms underlying the influence of nutrition on the epigenome,and subsequently on the expression of the genome, may help to influence dietary habits and behaviors.

But this work is even more thrilling that just that.  What if eating well could actually prevent cancer? What if it wasn't just a hunch and we had solid scientific evidence that vegetables and fruits prevent cancer?  Would you change the way you eat?  The researchers continue,

A key aspect of this work, which raises much excitement, is the potential reversibility of aberrant epigenetic modifications in cancer cells. We are only beginning to understand how epigenetic manipulations by dietary compounds can help us to live a healthier and longer life. Annu Rev Nutr 2008;28:347-66.

Don't wait for the all the research to come in. We have enough information to act.  Eat well now.

Saturday, January 16, 2010

FDA on BPA- Oops!

The US Food and Drug Administration carries the tag line, "Protecting and Promoting Your Health."  They tried to sway the public's concern one year ago by defending the safety of bisphenol A (BPA).  Although the research was robust even a year ago, they stuck to their guns and said there was no legitimate cause for concern.  To their credit, they recently reversed that position and acknowledged potential harm to consumers.  BPA is a compound found in plastic bottle, cans and plastic food containers.

Their statement reads, "FDA shares the perspective of the National Toxicology Program that recent studies provide reason for some concern about the potential effects of BPA on the brain, behavior, and prostate gland of fetuses, infants and children."


The FDA is now:
1.  Supporting the industry's actions to stop producing BPA-containing bottles and infant feeding cups for the U.S. market.


2. Facilitating the development of alternatives to BPA for the linings of infant formula cans.

I'm glad that the FDA finally acknowledges the concern. It kind of makes you wonder what other chemicals are leaching into our bodies.  What are the effects?

Tuesday, January 12, 2010

Is a large bottom healthy?

Recent headlines:
"Obesity study shows big bottoms and thighs can be healthy"  USA Today
" Junk in the trunk could be good for the heart"  Toronto Star
"Having a big bum, hips and thighs is healthy" BBC News

A new study suggests that body fat in the buttocks and thighs may actually be beneficial!  It is surprising but not an entirely novel idea.  Scientists have often talked about "apples" and "pears" in reference to the fact that belly fat presents significant metabolic risks. But before you get swept away in the hysteria and start reaching for the ice cream, let's get some expert reaction.

"If you're going to have fat, you're definitely better off if you've got some fat in the lower body," Dr. Michael Jensen, director of endocrine research at the Mayo Clinic in Rochester, Minn.

"I think that the article makes a fairly compelling point that there are likely differences between these two fat stores... But I think it certainly falls short in making a convincing argument that one is protective and the other is the major source of the problem." Floyd Chilton, a professor of physiology and pharmacology at Wake Forest University Baptist Medical Center in Winston-Salem, N.C.   (source ABC news)

Nobody is saying that butt fat is good for you.  They're saying that butt fat acts differently than belly fat and may be "not as bad."  The implications that butt fat is "good" for you is based on a narrow view of only 1 or 2 variables and does not compare people with butt fat to thin, healthy populations. 

The research article states, " Finally, loss of gluteofemoral fat, as observed in Cushing's syndrome and lipodystrophy is associated with an increased metabolic and cardiovascular risk."

But for those of you who do not have Cushing's syndrome or lipodystrophy, I would encourage you to reduce body fat wherever it is located.

Thursday, January 7, 2010

Nutrition vs. Exercise

A study published through the American College of Sports Medicine explores the relationship between improved nutrition, weight loss and exercise.  In brief, the researchers prescribed the following interventions between two groups (and a 3rd control group):
1.  Group 1:  improved nutrition
2.  Group 2: improved nutrition plus regular exercise

When outcomes were measured 6 months later, both groups had lost weight and body fat.  However, the group that included regular exercise saw significant improvements in metabolic factors such as blood pressure, LDL cholesterol and insulin sensitivity. 

In other words, a healthy diet alone is good. Diet plus exercise is so much better.  A real shocker, huh?

It's the season of New Year's resolutions and throngs of people are flocking to gyms across the United States.  I have a lot of admiration for individuals who are committed to building strength and fitness.  But while this study seems to suggest that exercise MUST accompany good nutrition, I'd like to say it the other way around as well.... Good Nutrition Must Accompany Exercise.

Please don't fool yourself by treating yourself to a cheesecake "since you just had a great workout."  Exercise doesn't give you permission to eat poorly.  It gives you opportunity to experience compounding returns on your investment of time and energy.  As we start the new year and you finish your workouts, eat well.