Is it possible to feel sorry for sugar? Much craved after, yet blamed for many ills, maligned for its ubiquity, and ostracized from the diets of the strong-willed.

I don’t think sugar in itself is a bad thing. I think that eating too much is the problem.

Ask any diabetic, and they will confirm that fluctuations in blood sugar can cause irritability, sadness, nervousness, and low moods. Moreover, many people who have insulin resistance but are not yet diabetic can still experience effects on their mental health. Even non-diabetics experience blood sugar effects on mood. Most of us are familiar with terms like “sugar high” and “sugar crash.”

In an article in the Psychiatric Times titled “Diabetes Takes Its Toll,” Dr. Alisa Woods wrote, “[P]ersons with bipolar disorder have up to a 3-fold elevated risk for type 2 diabetes mellitus, and 53% of bipolar patients have pre-diabetes or diabetes. It comes as no surprise then, that cardiovascular disease is the leading cause of death in persons with bipolar disorder.”

Turning to a research article, “The Impact of Sugar Consumption on Stress Driven, Emotional and Addictive Behaviors,” we find that eating too much sugar is correlated with depression, anxiety, and cognitive impairments, such as poor memory. Rat studies imply that excess dietary sugar could lead to decreased formation of new neurons, which could explain why cognitive impairments can occur with high-sugar diets.

Yet another study upheld the association of sugar intake with depression but (interestingly) not that of sugar intake with anxiety – thereby contradicting the previous article. Here is a quote that gives a decent overview of the mechanisms by which excess sugar may affect one’s mental health:

Rapid fluctuations in blood sugar activate the stress response and increase cortisol secretion, affecting mood stability. Additionally, sugar impairs the function of the hypothalamic–pituitary–adrenal (HPA) axis, a crucial component of the neuroendocrine system. This impairment can lead to stress and metabolic disorders, such as obesity and diabetes, contributing to oxidative stress and inflammation. Prolonged sugar intake may also trigger systemic and neurological inflammatory responses. Elevated inflammatory factors, such as TNF-αand IL-6, are strongly associated with the development of depression. Chronic inflammation can disrupt neuroplasticity in the brain, potentially leading to depressive symptoms. Moreover, the brain–gut axis theory suggests that a high-sugar diet alters the composition of the gut microbiota, reducing beneficial bacteria and increasing harmful bacteria.Studies on the gut–brain axis have shown that gut microbiota dysbiosis can influence brain function and mood regulation through the release of inflammatory factors and metabolites. Additionally, sugar intake may lower levels of brain-derived neurotrophic factor (BDNF), essential for neuroplasticity and emotional regulation. A decrease in BDNF levels is associated with the development of depression.

However… just when you may have concluded that you have a good picture of just how treacherous sugar is and how it wreaks havoc on your body, more research throws a wrench into the matter. Turns out that too little sugar can be problematic as well. Yes, excess sugar can increase one’s risk of mental health decline, but so can a deficit of sugar!

So, now you may be wondering what is the healthy range of sugar intake? Luckily, they provide this data. It is 23-160 grams, or 5.5 tsp to 38.4 tsp, per day, with no more than 21.5 tsp of added sugar. So, having a slice of cheesecake or pie or some chocolate is, apparently, not a problem! Hurray! That said, to those with mental health issues related to sugar, I would recommend trying out the lower end of that range for starters – just to be on the safe side.

All of this research begs the question–

What if these psychiatric diagnoses are essentially a straw man?

What if, for a number of people, the reason for their poor mental health is (among other things) years of unhealthy eating habits that have culminated in unstable blood sugars, and that is why they are getting chaotic moods, anxiety spells, and episodes of depression?

What if, should the blood sugar be fixed by improving the diet and adding exercise, these mental health issues went away?

There’s really only one way to find out, and that is by adapting a lifestyle change.

The mentally ill population is disproportionately obese compared with the general population

Compared to the general population, people designated as seriously mentally ill (or SMI)

have three times the obesity rate. This is according to data compiled from 43 countries. Another study reports:

Over 80 percent of people with serious mental illnesses are overweight or obese, which contributes to them dying at three times the rate of the overall population. They succumb mostly to the same things the rest of the population experiences—cardiovascular disease, diabetes and cancer. Although antipsychotic medication increase appetite and cause weight gain in these patients, it is not the only culprit. Like the general population, sedentary lifestyle and poor diet also play a part. Lifestyle modifications such as diet and exercise should work for these patients, yet they are often left out of weight loss studies.

The relationship between weight gain and antipsychotics is more serious than they let on, but I will get to that in a bit. First off, I would like to point out that the relationship between unhealthy eating and poor mental health is circular. That is to say, feeling bad may incline a person to eat more dopamine-stimulating foods (sugary, fried, fatty foods) in order to feel better, and eating an excess of these calorific, low nutritive foods may in turn lead to a further decline in mental health. Unhealthy eating habits can lead to insulin resistance, prediabetes, and type 2 diabetes (in order of worsening condition). If you are overweight or obese and also sedentary, then your chances of getting one of these health conditions is high.

As for antipsychotics, these worsen the situation through more than merely boosting the appetite; they are actually known for side effects of causing metabolic and blood sugar issues. Zyprexa (or olanzapine) comes with a 71% higher risk of diabetes! According to a psychiatric provider who was a former colleague of mine, it is normal for people to put on 20 pounds right away after starting anti-psychotics. If I remember right, he said this occurs within the first couple of months.

What does the rate of obesity/overweight look like for the untreated? Well, according to this Italian study, about 41% of drug-naive (meaning they did not take psych drugs) bipolar patients were overweight or obese and just under 11% of OCD patients. That is a stark contrast from the 80% figure presented above.

How to know if you are diabetic or on the way there?

Here are common symptoms of insulin resistance:

• Getting tired after eating
• Bloated after eating
• High cholesterol
• Hungry after eating
• Patches of dark skin (acanthosis nigricans)
• Skin tags
• And, of course, mood swings.

What can you do to reverse course?

From my personal research into nutrition, here are some solutions. None of these are prescriptive, just common sense suggestions.

1. Structure your diet primarily around food that is low on the insulin or glycemic index. I am not saying one should go keto; that is up to you. Research the glycemic index and insulin index of foods and adjust your choices as needed.
2. Move more. Do an exercise of your choice. Walking, gardening, riding a bicycle, hiking, swimming, dancing, etc. Yoga is very popular, but I do not recommend it for this reason. I suspect that it’s difficult for many people to stick to an exercise routine because we prefer to engage in goal-oriented activities for an immediate purpose. To illustrate, I imagine it would be easier for most people to walk or bike to work everyday (if the distance is reasonable) than to plod along on a treadmill in their living room.
3. Reduce simple carbohydrate and sugar intake. It might help to view these as occasional treats, rather than staples. So, maybe don’t have a slice of cheesecake or a candy bar every day but rather some fresh or dried fruit or sweet potatoes to satisfy one’s sweet tooth.

If you are experiencing poor mental health and you eat a lot of sugar, try cutting back to see what happens.

Did you find this article helpful? Here are some more that may interest you: