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Obesity, Genetics, Depression and Weight Loss

Stress and Weight Gain

In addition to unresolved depression causing real biological changes — which in turn cause weight gain — we now know that stress and anxiety do the same thing. Stress doesn’t cause changes to our metabolism like depression does, but it does cause changes to the way our body decides to burn fat. When under stress, our brain releases a hormone called cortisol. This hormone sends a signal to our body to store fat rather than burn it (Björntorp & Rosmond, 2000). There’s also evidence that not getting enough sleep can cause our brains to release cortisol (Cauter et al., 2005). The stress we experience about work, school, family, and relationships is literally making us fat.

In modern society it seems strange that our body would see weight gain as an antidote to stress. In order to understand this, we have to understand the type of world we were living in when our body evolved this response. Before modern agriculture and technology, if we were under stress it was probably due to famine or other environmental issues that could lead to our dying of starvation. Throughout much of human history, dying of starvation was the No. 1 stressor and No. 1 threat to our survival. It was thus essential to our species’ survival that our bodies react to stress by conserving energy. The types of stressors we have now either didn’t exist or weren’t important enough to us back then.

Fortunately, there are ways that we can reduce cortisol. The most obvious way is to reduce stress levels. Talk therapy has been shown to be an effective way of reducing cortisol levels (Littrell, 2008). Other ways of reducing cortisol include exercise, meditation, and yoga. The important thing to take away from this is that so long as you are experiencing stress and anxiety, your body is going to do everything it can to prevent you from losing weight. This can be especially problematic if you are exercising and dieting in such a way that causes you stress and anxiety and keeps you up at night.

Feeling bad about the way you look and putting lots of pressure on yourself to lose weight simply isn’t going to work. A lot of people decide that they want to lose a large amount of weight immediately and go through drastic measures to do it. What they don’t understand is that those drastic measures are causing them loads of stress and anxiety, really the opposite of what you want to do to yourself in order to lose weight. You also can’t expect to be able to successfully lose weight if you’re living in a chaotic and stress-filled environment. If you truly want to be able to lose weight and keep it off, you need to work on your emotional health first.

Food as an Addiction

Whenever we are talking about addiction, we are talking about two things: tolerance and withdrawal. Tolerance simply means that over time it takes more “drug” in order to produce the same “high” you got the first time you used the “drug.” Withdrawal refers to the unpleasant symptoms a person experiences when they try to wean themselves off of the “drug.” Physical symptoms of withdrawal can include headaches, pain, nausea, and diarrhea. Emotional symptoms of withdrawal can include irritability, sadness, and anxiety. A good rule of thumb is that you can expect the withdrawal symptoms to be the opposite of what the “drug” does to you. So for instance, if a drug makes you feel less anxious, you can expect one of the withdrawal symptoms to be increased anxiety. If a drug causes you to fall asleep, you can expect insomnia to be a withdrawal symptom.

We experience tolerance and withdrawal because of very real changes in our brain. Your brain wants there to be a balance. When it senses too much of a certain chemical, it responds by decreasing its own production of that chemical. Drugs affect our brains because they mimic naturally occurring pleasure-inducing chemicals like dopamine, endorphins, serotonin, and norepinephrine. When the brain is artificially flooded with these chemicals, it doesn’t like the imbalance, so it responds by producing fewer and fewer of these chemicals on its own. That is why addicts eventually gets to the point when they need to take drugs just to feel normal, because the brain has stopped producing these important chemicals on its own.

Due to advances in technology, scientists now know that these same processes of tolerance, withdrawal, and real chemical changes in the brain happen in food addiction just like they do in drug addiction (Gearhardt & Corbin, 2011). Tolerance is manifested in food addiction in a couple of different ways. One way it is manifested is when people need to eat more and more food in order to feel full or satisfied. Another way is when people are unable to derive pleasure from eating healthy foods. We are biologically wired to find fruits, vegetables, and whole grains pleasurable, and feeling like these foods are “tasteless” is a sure sign of tolerance. Withdrawal symptoms in food addiction typically results in feeling hungry even though you are already nourished, headaches, mood swings, irritability, depressed mood, and anxiety. No wonder people have such a hard time sticking to diets!

Critics of food addiction point out that if food has addictive qualities, why is food addiction such a new phenomenon? And why is it just humans who seem to be susceptible to it? After all, all animals eat and we’re the only ones who seem to have a problem with obesity and food. Well, the reason is because the food we are eating today is drastically different from the food people have eaten throughout most of human history.

Genetically modified foods have only been around since the 1980s. Highly processed foods and so-called “convenience foods” are also a relatively new phenomenon. They didn’t come on the market until around the 1960s, and that is also when researchers started noticing an increase in rates of obesity. These processed “convenience foods” are loaded in salt, sugar, and fat. And it’s not just convenience foods that are to blame. For instance, the meat found in wild game (the type of meat that our ancestors used to eat) only contains about 10 percent fat. Compare that to a slab of meat you buy in the grocery store that is as high as 50 percent fat.

Our bodies are no different than they were a hundred years ago, but the food we are eating is. And when we’re eating these highly processed foods, it’s been shown, the reward centers of our brains light up just as if we had ingested cocaine (Lenoir, Serre, Cantin, & Ahmed, 2007). When we eat such unnatural foods, our bodies have an unnatural reaction.

The prevailing attitude toward obesity is that people just need to straighten up and take responsibility for their own behavior. Society used to have that attitude towards alcoholism and drug addiction and it was that same attitude that held back the recovery movement for a very long time. We need to have the same attitude shift in regards to food addiction and obesity. There’s no such thing as “eating in moderation” and “just practice self-restraint” when it comes to addictive foods. That attitude hasn’t worked for alcoholics and it won’t work for food addicts either.

So at this point you might be wondering, “So what do you do if you’re addicted to food?” Unfortunately, you have to do many of the same things a drug addict would have to do in order to recover. You first have to accept that you can’t eat even a little of the addictive foods. You are going to have to practice abstinence when it comes to these foods and unfortunately deal with the withdrawal symptoms until your brain chemistry becomes normal again. A therapist can teach you tricks and techniques for lessening these withdrawals and avoiding relapse.

Weight Loss and the Placebo Effect

A placebo typically refers to a “sugar pill,” or fake medical intervention. When researchers are testing the effectiveness of a new drug, they’ll assign half of their volunteers to receive the actual medication and the other half will receive the placebo. The researchers won’t tell the participants whether they received the real medication or the placebo until the study is over, so during this time the participants taking the placebo think that they are taking the real medication.

The interesting thing about this is that in these studies, even though the participants aren’t actually receiving any real treatment, they still get better simply because they believe that the placebo is a real medication. The fact that these people are able to benefit simply by believing they will is known as the placebo effect. Again: The placebo effect is when people experience real biochemical changes in their body simply because they believe that they will.

We know that the weight loss people experience when they take over-the-counter diet pills is entirely due to the placebo effect, and yet people do lose weight simply because they believe they will. A lot of people take the attitude that “hey, I’ll do whatever works.” So if diet pills “work,” even if it is just by placebo, people will see no harm in taking them anyway. The problem with this is that diet pills can be quite harmful. Diet pills have been known to cause liver failure, strokes, seizures, and even death. Researchers have found that there are safer ways of producing placebo-driven weight loss.

In one famous study, a Harvard psychologist proved that people can actually think themselves thin. The psychologist enlisted the help of 80 hotel maids. Half of the maids were randomly assigned to a control group, meaning that they received no treatment. She met individually with the other 40 maids and went over what they did on a daily basis for exercise and how many calories they ate a day. The psychologist then told these women that they were burning more calories than they were eating, so she expected that they should lose weight without having to make any changes. The psychologist was actually lying when she said this, but she wanted to know if the women would lose weight simply because they believed they would.

As it turned out, they did. She asked the participants to keep a log of their daily exercise and calorie intake to make sure that they simply hadn’t changed their behavior and that that was causing the weight loss. The only thing that had changed was the maids’ mindset. Amazingly, the participants not only lost weight but they lost inches off their waist and even had a drop in blood pressure (Shea, 2007).

Another study on the effects of positive thinking on weight loss found similarly positively results. In the study, participants were asked to do daily visualizations where they imagined themselves having more positive interactions with food and being able to successfully resist temptation. Those using positive thinking lost an average of 26 pounds more than the control group after a year (Oettingen & Wadden, 1991). It is becoming more and more clear that you can lose weight simply by changing the way you think.

If you are still not convinced that you can lose weight simply by changing your thinking, let me tell you about another study. Ghrelin is the biochemical responsible for making us feel hungry. When levels of ghrelin are low, we feel satiated. When they are high, we want to eat more. In this study, when researchers told participants that the milkshake they were about to eat had a lot of calories in it, the participants’ ghrelin levels dropped. When participants were told that the number of calories in the milkshake was very low, ghrelin levels increased. The chemical that causes us to feel hungry is not regulated by the number of calories we eat, but rather our perception of how many calories we eat (Wang, 2012). You can see why mindless eating can cause someone to become obese. Not being aware of how many calories we are consuming can cause us to feel hungry even though we’ve already eaten plenty.

Obesity, Genetics, Depression and Weight Loss

Marina Williams, LMHC

APA Reference
Williams, M. (2018). Obesity, Genetics, Depression and Weight Loss. Psych Central. Retrieved on January 19, 2019, from
Scientifically Reviewed
Last updated: 8 Oct 2018
Last reviewed: By a member of our scientific advisory board on 8 Oct 2018
Published on Psych All rights reserved.