Bipolar depression may be metabolic in origin

A pilot study involving 27 people found that the ketogenic diet helped alleviate symptoms of bipolar depression (or manic depression), suggesting that it may be metabolic in origin. Experts concluded that this devastating health problem could therefore be treated as a physical disorder rather than a mood disorder, potentially making it easier to manage.

Bipolar depression (also called manic depression, bipolar disorder, or manic-depressive illness) is characterized by mood swings that range from one extreme to another. The “high” mood (the manic phase) is characterized by an excess of energy, while the “low” mood (the depressive phase) is characterized by sudden, intense lethargy. Sometimes people have no energy. Other times they just have too much. They are manic. They don’t need sleep. They are very active and sometimes do things that are out of character for them. “This extreme mood swing puts patients with the disorder at high risk of suicide,” Danny Smith, director of the Hub for Metabolic Psychiatry at the University of Edinburgh, told the Guardian.

The disorder typically manifests between the ages of 15 and 25 and affects both men and women. It is estimated that 1 to 4% of the world’s population is manic depressive. However, this statistic may not be accurate due to its tendency to be confused with other disorders, such as borderline personality disorder, which is also characterized by extreme mood swings.

The causes of the disorder include a combination of psychological, genetic, and environmental factors. Recently, it has also been suggested that it may be metabolic in origin. For example, studies have shown that people with manic depression have abnormal glucose metabolism and an increased predisposition to insulin resistance and type 2 diabetes. Hyperinsulinemia may impair energy production by mitochondria in the brain, which could lead to the fluctuating symptoms of the disorder.

” We should view bipolar depression not as a primary emotional problem, but as a dysfunction of energy regulation in the body.
“, says Iain Campbell, co-author of the pilot study, who helped create the Hub for Metabolic Psychiatry.
This is a very different way of thinking about mental illness. ” he adds. Because ketones can provide an alternative energy source to glucose, Campbell and colleagues have suggested that the ketogenic (or keto) diet may help stabilize mood in people with manic depression.

Symptoms alleviated after 8 weeks of ketogenic diet

The ketogenic diet consists of favoring foods rich in fat and limiting those rich in carbohydrates. Common ingredients include, for example, avocado, oily fish (salmon, mackerel, etc.), eggs, low-carb vegetables (broccoli, spinach, asparagus, etc.), nuts, and dairy products. The goal is to induce ketosis, a process in which mitochondria preferentially oxidize fatty acids to produce ketones, which are used instead of glucose as an energy source. Commonly used for weight loss, recent studies have shown that this diet can also induce metabolic changes that can reduce seizures by 50% in children with drug-resistant epilepsy. Beneficial effects have also been observed in patients with schizophrenia.

Given that the pathological processes of these disorders share similarities with those of bipolar disorder, the ketogenic diet could potentially alleviate its symptoms. In particular, it is suggested that the diet may affect metabolic and biochemical features of bipolar depression, such as reducing oxidative stress and improving mitochondrial function.

To test these hypotheses, Campbell and his colleagues invited 27 people with bipolar disorder to follow a ketogenic diet for 8 weeks. The results, published in the journal
BJPsych Openshowed that 91 percent of participants were in ketosis and had normal blood sugar levels throughout the experiment. On the other hand, “a third of them responded very well. Their mood was more stable, they were less impulsive, and their depression was reduced,” Smith said. The next step in the study will be to determine why some patients responded well to the diet while others did not.

A potential involvement of the circadian rhythm

The Hub for Metabolic Psychiatry will also aim to study the links between bipolar depression and metabolic disorders, such as obesity and diabetes, as well as circadian rhythm disruption. The systems involving energy, metabolism and light are all interconnected in our body and one of the consequences of their disruption is, we believe, bipolar depression. “, Smith explains.

Indeed, many bipolar people’s depressive episodes seem to peak in the fall and winter, while their manic episodes typically increase in the spring. This suggests that the fluctuation in the disease’s symptoms may be related to circadian rhythm. On the other hand, patients have reported that light and colors tend to trigger their manic symptoms during certain times of the year.

To explore these hypotheses, the team plans to analyze in the laboratory the response of retinal cells of bipolar patients to light and seasonal changes. Radar technologies will also be used to monitor the physiological dynamics of the patients’ sleep for about 18 months. These analyses will make it possible to identify the physiological variations induced by their mood changes and, ultimately, improve the prevention of these changes.

Source: BJPsych Open