I recently came across a fascinating study that Stephan Guyenet mentioned in an article in his series on the neurobiology of eating. In this study, the researchers found that half of annual weight gain in the U.S. occurs during the holiday period.

That is a sobering statistic in itself, but what makes it even more significant is the fact that most of this weight is retained indefinitely. People tend to lose a little bit in January when the holidays are over, but the rest of it sticks around. Even modest increases like this each year can add up over time. The average American gains between 0.5 and 1.75 pounds a year, and a National Health and Nutrition Examination Survey follow-up study found that among adults 25 to 44 years old, the body weight measured at 10-year intervals increased by an average of 3.4 percent in men and 5.2 percent in women (1).

But there’s evidence that holiday weight gain is even more of a problem for those that are already overweight or obese. People that gain 5 pounds or more during the 6-week holiday period are more likely to be obese or overweight than those that gain less. (2) It’s also well-established that weight loss programs are less effective over the holidays than at other times of year. (Duh.)

In a previous radio show episode called Why It’s So Hard To Lose Weight – And Keep It Off, I discussed the concept of the body fat setpoint.

From an evolutionary perspective, survival in a natural environment is threatened by either too little or too much fat. If we have too little fat, we can’t survive periods of food scarcity and we starve. If we have too much fat and we become obese, then we aren’t as fit to hunt and gather food and evade predators and survive.

The body fat setpoint is a mechanism that helps us maintain an ideal weight appropriate for the human ecological niche. When our weight increases above this setpoint, the brain engages various mechanisms to decrease it – and vice versa. This is how normal weight people are able to maintain virtually the same weight throughout their entire life without counting calories coming in or going out.

In overweight or obese people, however, the setpoint is broken. Instead of defending an ideal weight, the setpoint gradually creeps up over time. There are many theories about why this happens, but one novel possibility that Stephan speculates on in his article is that weight gain itself increases the setpoint over time.

If this is true, it has profound implications. Something as seemingly innocuous as picking up a few pounds over the holidays could increase the weight that the body defends. This could explain why it’s so difficult for people to lose the weight they gain over the holidays; their body is holding on to that weight as if its survival depended on it (remember: the body fat setpoint is essentially a survival mechanism).

This means it’s crucial – especially for people that are already overweight – to avoid holiday weight gain if your goal is to maintain your current weight or lose weight.

Half of all annual weight gain in the U.S. occurs during the holiday period.

How to prevent holiday weight gain

Now that we’ve established how important it is to avoid weight gain during the holidays, let’s look at some strategies for keeping it off. Remember, there’s no one-size-fits-all approach to diet and nutrition. The recommendations I’m making here are not for normal weight, healthy individuals. They are for people that are already overweight and/or have a tendency to gain weight easily. In those cases, we might suspect that the homeostatic system that regulates weight is impaired in some way, and a specialized approach is required.

Some of these recommendations may surprise you if you believe that calories don’t matter and weight gain is not possible as long as you’re eating a nutrient-dense, low-carbohydrate diet. I used to think this was true myself, but after further research and more experience working with people in my clinic, I now know that it is not. If you’re confused about this, please listen to the podcast I linked to above (or read the transcript); it will clear things up.

Eat more simply

One of the biggest reasons people overeat during the holidays is because of the abundance of highly palatable and rewarding food. A food is palatable when it tastes good. A food is rewarding when it makes us want to eat more of it.

Palatability and reward usually travel together, but there are exceptions. For example, most people think steak tastes good, but it doesn’t tend to encourage eating beyond satiety.

Choosing foods that are lower on the reward value scale during the holidays is one way of spontaneously reducing your calorie intake. But what makes a food rewarding? There are several factors, including:

sugar, fat and salt content

calorie density

certain textures (fat that melts in mouth, crunchy, soft/easy to chew)

free glutamate

starch

certain aromas

variety of flavors, textures, foods

many other flavors can become rewarding when associated with above nutrients

Looking at that list, it’s not hard to see why holiday meals would promote overeating!

With that in mind, here are some tips for eating more simply during the holidays: