I’m finally back from the holidays, as I’m sure are most of you. I put on a few pounds in the past month, so sue me. I may be a nutritionist but I’m also human! We all want to lose a little or a lot of weight at this time of year (a boom time for health clubs and gyms), as our holiday indulgences eat away at our guilt, pun intended. In my last post of 2017, I promised to address the pertinent issue of how to lose weight and keep it off, and I shall now make good on that promise.
First, it seems apropos to first discuss the economics of weight loss and the multi-billion-dollar industry built around this ubiquitous ambition that pervades the very fabric of our society, personally, economically, psychologically, sexually, and even politically. Weight loss is not just a personal goal, it’s a big business, one which promotes financially lucrative modalities, not science. The metabolic biology of burning adipose tissue as a fuel source has nothing whatsoever to do with Jenny Craig, Nutrasystem, or Oprah Winfrey!
So here’s the skinny on weight loss (I have many more bad puns where that came from!). At its most fundamental level, weight loss is simply about the laws of thermodynamics and E=mc2. Matter converts to energy. That matter can either come from food or from stored adipose tissue. Any questions? Good. Let’s move on.
Now one might posit, based on what I just said, an overly simplistic notion of weight loss. Eat less food, burn more calories than you consume, and you will lose weight. Seems simple, right? I wish it were. For indeed there are numerous confounding variables embedded into the metabolic equation. In fact, there are circumstances in which one can actually consume fewer calories than one burns and still put on body fat, such as when we consume foods that spike our insulin levels, such as high-glycemic carbohydrates. Insulin is an energy storage hormone. If you are a Tour de France cyclist riding 100+ intense miles/day, insulin will tell your body to store circulating glucose as glycogen in your hard-working muscles. But if you’re a sedentary sloth binge-watching Game of Thrones, that same quantity of circulating glucose will be converted to triglycerides and stored as body fat, even in the context of a caloric deficit. Bummer, isn’t it? Here’s one more thought that will blow up your brain. We are ALWAYS, throughout the day, either in a state of fat burning (lipolysis) or fat storage (lipogenesis), like it or not. When in fact you do lose weight, all it means is that you spent more time in a state of lipolysis than lipogenesis within any given 24-hour period. But this also does not mean that our bodies operate on a strict 24-hour cycle of fat burning and fat storage that is partitioned from one day to the next. In fact, recent studies have shown that caloric deficits and excess span a quantifiable period of 5-7 days in terms of metabolic impact.
So now let’s bump this up another level and talk some more about hormones. The laws of thermodynamics are great but our bodies are not steam engines. The main thing that differentiates us from steam engines is hormones. Hormones can do some weird stuff to our bodies. They can become schizophrenic and sabotage our efforts to lose weight. A few that are worthy of mention include insulin, as mentioned previously, leptin, which tells our fat cells to stop taking in triglycerides (such as when we try to starve ourselves), stress-induced cortisol, which increases blood sugar and carb cravings, grehlin, which tells our brain that we are satiated (broken in most overweight folks), adiponectin, which lowers blood sugar and burns body fat, and Hormone-Sensitive Lipase (HSL), which in adipose tissue is normally inhibited by low levels of insulin. Catecholamine, cortisol, growth hormone and glucagon activate this enzyme. Fasting and an energy deficit tend to progressively reduce insulin and elevate the abovementioned counter-regulatory hormones, which triggers lipolysis, i.e. weight loss. Confused yet? Don’t worry. I’ll break it down for you in a moment.
The proverbial bottom line is this. Burning body fat is not about eating less and exercising more, although that does create a favorable environment in which our hormones can communicate with each other. Mostly it’s about telling our hormones that we are not starving to death, because our body’s Number One priority is always self-preservation, but when we don’t quite have enough to eat to sustain our daily activities, we must discretely tap into our precious reserves of body fat to keep us going. Now please keep in mind that this all needs to be viewed through the evolutionary lens of our ancient ancestors relying on stored body fat to get them through harsh winters when food sources were scarce, so stored body fat is not a biological aberration, it is in fact a survival mechanism. These days, our higher brain functions compel us to look like lean mean fitness models, however our hormones are still stuck in the Paleolithic era. But please don’t get me wrong. I am not advocating the wildly popular “Paleo Diet”. I’m merely saying that every organism on Earth evolved to survive and thrive within a specific ecosystem, be they insect or human. When we screw with our millennia-old ecosystem by putting up a McDonald’s on every other street corner, we have created the equivalent of stuffing a pride of lions into a hockey rink filled with Snickers bars. How long do you think those lions would survive?
So what should you do to lose weight and keep it off in this new year? Reread this blog post and use your critical thinking skills to come up with an action plan that is consistent with your genetic blueprint as a homo sapien!