Explain Nation: Why some dieters can be grumpy, and how they can feel better

I have a friend who was jolly when he was obese. After a very successful workout, he looked like a model from Vogue but he had the temper of a chef from Hell’s Kitchen.

My staff in the office came up with the trick to give me sugary food before they presented their concepts. They told me that the tactic always raised the probability of me approving their work.

Here are reasons why it’s not just a joke, not just a myth, that people who eat less can be in a bad mood.

1. Cortisol rising. This is the brain hormone that prepares the body for battle. When cortisol rises, more blood is pumped into body parts we need for fighting or running away. The heart beats faster and breathing becomes more rapid. Cortisol is triggered whenever the body senses danger. 

If we don’t eat enough, the brain may interpret it as a threat to our survival. So, the rise in cortisol may make us easily triggered by anyone or anything annoying.

2. Sugar changes everything. Sweet food makes us happy because in the early days of humankind, the brain encoded survival food to taste good.

Sugar was essential as a source of physical energy, while glucose is the main nutrient of the brain. But things have changed. We no longer need to walk miles looking for food and we don’t run away from tigers anymore. But our taste buds have not changed. Cakes, ice cream, and chocolate still taste good! So, the sugar that we don’t burn becomes fat that is often bad for our health. To dieters, sugar in sweets and carb-rich food is public enemy number 1.

Clinical tests have shown that craving for sugar is associated with low levels of dopamine and serotonin. Dopamine is the brain hormone that gives us a feeling of pleasure while serotonin is one of our happiness hormones. Deprived of happiness and pleasure, we may not become friendly enough.

3. Self-control is depleted. Some experts say that we can run out of self-control when we’ve been using such faculty for an extended period. For example, when you’re a diplomat trying to control your anger the whole day, you may be less likely to resist a cigarette.

So, some experts assert that resisting pasta and moist chocolate cake is too much self-control therefore you will have little left to control your anger.

4. Frustration. A few hours in the gym makes us so hungry. The brain would like to reward the tongue with pizza or chocolate chip cookies. But no way for calorie-counters! Frustrated is sometimes a synonym for angry.

Food deprivation can have serious consequences. The wrong medication may be just as dangerous. Robert H. Lustig, pediatrics professor at the University of California, mentioned in his The Atlantic article an anti-obesity drug called rimonabant. It blocked the effect of certain molecules on the brain’s pleasure center. Patients lost interest in food. But twenty percent became clinically depressed and some committed suicide.

There is a way to feel better

To achieve our fitness goal without fighting with our nutritionist, we can focus on the reward because thinking of a reward raises dopamine, the pleasure hormone. We can think of how a healthy heart can add years to our life, how we can climb the stairs without catching our breath.

It is also good to do things that make us happy. When I was yoyoing between anxiety and depression resulting in insomnia, my CBT psychologist noticed that I loved wearing nice-looking shoes. So, her advice to me was,” go buy more nice shoes and you may sleep better.” After my session, I would eat special pan de coco (bread stuffed with sweet coconut) at a cafeteria in the hospital. I would go home anxiety-free. I didn’t know if it was because of my therapy or because of the pan de coco. 

Finally, diet food can be yummy! Before the lockdown, I lost about 20 pounds just by eliminating rice and sugar from my diet. I was able to eat green salad at lunch for weeks because I was always searching for the best-tasting salad. The anticipation raised my dopamine levels. Of course, I also anticipated being able to button my blazers!

Read More:

Effects of sugar-rich diet on brain serotonin, hyperghagia, and anxiety in animal model of both genders on PubLMed.gov

Tame Your Anxiety: Rewiring Your Brain for Happiness by Loretta Graziano Breuning

The Most Unhappy of Pleasures: This Is Your Brain on Sugar by Robert H. Lustig on The Atlantic website

Understanding The Stress Response on the Harvard Health Publishing website

Willpower: Why Self-Control is the Key to Success by Roy F. Baumeister and John Tierney