Tailgates, holiday parties, horrible bosses, and stressful weeks. What do all of these have in common? For many people the common thread is some sort of alcohol consumption, whether modestly or not. Alcohol may help us unwind, help us have a good time, and make food taste really, really good. However, alcohol consumption, especially consuming alcohol regularly in large quantities, can also work directly against your weight loss goals. I’ll start by covering the obvious reasons why consuming alcohol can slow or even halt your weight loss progress:
You will drink extra calories.
There are three macronutrients: carbohydrates, fats, and protein. So which of these categories does alcohol fall into? Alcohol, in its purest form, is actually its own category. One gram of both carbs and protein contains four calories. One gram of fats contains nine calories—significantly more. One gram of alcohol contains about seven calories, and once you add in the other ingredients used to make beer or mixed drinks your calorie consumption begins to rack up quickly. A typical shot of liquor contains about 70 calories, 12oz of beer can contain anywhere from 100-300 calories, and some mixed drinks can contain upwards of 500+ calories for just a single drink!
You will eat extra calories.
We are all familiar with the fact that alcohol consumption blunts our inhibitions. Alcohol can also make food taste really, really good. These two scenarios combined lead to us make poor food choices, both in the types of food we choose (high fat/sugar) and in the amount that we consume. Who hasn’t drunkenly consumed an exorbitant amount of pizza?
While these facts may be the obvious ones, there are other ways in which alcohol consumption can negatively affect your weight loss progress. Let’s dig a little deeper into the physiological reasons why the next time you go out with friends you may want to nominate yourself as the “Designated Driver.”
Alcohol consumption causes an acute negative response to your body’s fat-burning mechanisms.1
What does this mean exactly? Alcohol negatively affects your metabolism. Alcohol is a toxin, and as a result your liver works overtime trying to neutralize it. The byproducts that are released as a result of this detoxifying process will blunt your body’s ability to burn fat (lipolysis). What does this mean for the extra calories you are consuming? It means the majority of these calories, instead of being used for energy, are going to be stored as body-fat.
Heavy alcohol consumption can affect workout performance for days afterward.2
With heavy drinking, it can take the body as much as 48 hours to eliminate the toxins from your body. As a result of your blunted metabolism, your muscles will receive less glucose to be used as energy. This means you will produce less force (have less strength), and reach fatigue faster during your workouts. Additionally, alcohol is a diuretic, which can lead to dehydration (a contributing factor for those nasty hangovers you may have experienced). Even mild dehydration is known to negatively affect exercise performance.3
Alcohol consumption can negatively impact the muscle-building process.
Heavy drinking can affect your ability to build muscle in two distinct ways. The first is your body’s ability to synthesize protein.2 Protein synthesis is the primary way that we generate new muscle. When we consume large amounts of alcohol, the rate of protein synthesis is decreased. Less protein synthesis = less muscle. Secondly, the more alcohol you consume, the more your body will decrease testosterone levels.4 Testosterone is one of the body’s sex hormones responsible for many things, including building lean tissue. When testosterone levels decrease, so does our ability to build muscle.
While there are many negative effects of drinking large amounts of alcohol regularly, this doesn’t necessarily mean I am advocating that you cease all alcohol consumption. In fact moderate alcohol consumption, defined as 1-2 drinks per day for men and 1 drink per day for women, has been shown to be beneficial to us in some ways.
Moderate alcohol consumption can boost insulin sensitivity.
We can think of insulin as the key that unlocks the cells so we can give them the nutrients from our food. If we develop insulin insensitivity we are essentially changing the locks to our cells, so that the keys we have no longer work. Moderate alcohol consumption has been shown to increase our sensitivity to insulin, ensuring our locks don’t change.5
Moderate alcohol consumption can help prevent disease.
Limiting alcohol consumption is a good idea for a healthy body and a successful fitness program. Substituting your usual cocktail for water at your next party (assuming you have 2-4 drinks) can save you between 300-600 calories! That can make a big difference to your weight-loss progress. However, moderate consumption of alcohol is probably going to be OK (from both a health and fitness perspective), given that you adjust your calorie intake accordingly.
About Alex McBrairty
Alex McBrairty is a personal trainer based in Ann Arbor, MI. He educates his clients in exercise, nutrition, and behavior change to help them develop new habits and reach their goals. Alex also teaches, writes, and speaks about fitness motivation and behavior change.