Long-term Depression Alters the Brain
Depression has become a common mental health problem. For some, this condition persists for many years, and scientists are now struggling to understand how that could affect the brain and how treatments should adjust to address these changes.
Depression can be progressive
Dr. Meyer and his team worked with 80 people between 18 and 75 years of age. Of these, 25 had lived with depression for more than 10 years, 25 had had the condition for less than a decade and 30 were free of depression. This final cohort constituted the control group.
In a 2015 study, Dr. Meyer and his colleagues saw that during episodes of major depression, the brains of people exhibited inflammation markers.
Active microglia produces the translocator protein (TSPO), which is a key marker of inflammation.
Through PET scans, Dr. Meyer and his team discovered that the concentration of TSPO was 29-33 percent higher in the brains of people who had lived with depression for more than a decade.
These markers of inflammation were observed in three regions of the brain in particular: the prefrontal cortex, the anterior cingulate cortex and the insula.
According to previous findings, the brains of those who had lived with untreated depression for shorter periods of time still had higher TSPO concentrations than the brains of healthy controls.
“Increased inflammation in the brain is a common response with degenerative brain diseases as they progress, as with Alzheimer’s disease and Parkinson’s disease,” says Dr. Meyer.
If depression, although not a neurodegenerative disease, is similar to such conditions, that is, it is characterized by an increasingly severe inflammatory response in the brain, then it may be appropriate to treat it with anti-inflammatory medications, suggests Dr. Meyer.
Therefore, he argues that other studies should consider the possibility of reusing such medication as therapy for depression.
Belly Fat Linked to Vitamin D Deficiency
A new study reveals that individuals with higher levels of belly fat and larger waistlines are more likely to have lower vitamin D levels.
Recent studies have found that vitamin D might protect against heart failure, diabetes, and cancer, and that vitamin D deficiency causes hair loss.
Understanding vitamin D deficiency
As vitamin D’s importance becomes ever clearer, researchers are dedicating more and more time to understanding who might be most at risk of deficiency and working out ways to prevent it.
A link between obesity and lower vitamin D levels has previously been spotted. Rafiq and team, dug a little deeper; they set out to understand whether the type and location of fat played a role. To do this, they took data from the Netherlands Epidemiology of Obesity study, including thousands of men and women in ages 45–65.
The team focused on total fat, abdominal subcutaneous adipose tissue (belly fat under the skin), visceral adipose tissue (around the organs), and hepatic fat (in the liver).
During their analysis, they adjusted the data for a range of potentially confounding variables, such as alcohol intake, smoking, ethnicity, education level, chronic disease, and physical activity levels.
Vitamin D and belly fat exposed
They discovered that in women, both total and abdominal fat were associated with lower vitamin D levels, but that abdominal fat had the greatest impact. In men, however, lower vitamin D levels were significantly linked with fat in the liver and abdomen.
Across both sexes, more belly fat predicted lower levels of vitamin D.
Rafiq explains, “The strong relationship between increasing amounts of abdominal fat and lower levels of vitamin D suggests that individuals with larger waistlines are at a greater risk of developing deficiency, and should consider having their vitamin D levels checked.”
Her next step is to understand why this relationship exists. Does a deficiency in vitamin D cause fat to be stored in the abdominal region, or does belly fat decrease levels of vitamin D? It will take more work to tease apart cause and effect.
As Rafiq explains, “Due to the observational nature of this study, we cannot draw a conclusion on the direction or cause of the association between obesity and vitamin D levels.”
“However, this strong association may point to a possible role for vitamin D in abdominal fat storage and function.”