As if depressed or anxious people needed another thing to worry about, a new study from UC San Francisco suggests that depression and anxiety may be as bad for the health as smoking or obesity.
First author Dr. Andrea Niles and senior author Dr. Aoife O’Donovan of the UCSF Department of Psychiatry and the San Francisco VA Medical Center examined the records of 15,000 adults over four years. Of that sample, 16% were found to be noticeably depressed or anxious. Compared to their non-depressed, non-anxious counterparts, those 16% of respondents were 65% more likely to have a heart condition, 64% more likely to have had a stroke, 50% more likely to have high blood pressure, and a whopping 87% more likely to have arthritis.
(They were not found to be at greater risk for cancer, but that’s not much of a silver lining, considering.)
Clearly, depression and anxiety are not a simple bad mood, or a weakness of character, but a serious medical condition. Clearly, something must be done. But where do we start?
In addition to all the conventional wisdom—therapy, meditation, sleep, exercise, medication—scientists have found a relatively new lead: the gut. Researchers at Northeastern University believe they’ve found a key link between mood disorders and the tiny, teeming world of the gut microbiome.
First, Phillip Strandwitz and Professor Kim Lewis of Northeastern worked with a team at Weill Medical College to gather fecal samples and brain scans from people with clinical depression. In examining the data, they saw that individuals with certain brain patterns associated with depression also had fewer gut bacteria of the genus Bacteroides.
There are about 100 trillion bacteria in the human digestive tract, of many different varieties; why were they keeping an eye on Bacteroides? Strandwitz and Lewis had previously discovered that Bacteroides produces a neurotransmitter called gamma-aminobutyric acid, or GABA for short. GABA interrupts signals being sent from your nerves, preventing your brain from getting overstimulated. The result is a calm, peaceful feeling—basically the opposite of depression or anxiety.
“If you have low levels of these GABA-producing bacteria, that is associated with brain signatures of depression. It’s a pretty strong correlation,” Lewis told Neuroscience News. “That opens up the intriguing possibility of treating depression with GABA-producing bacteria.”
If that sounds wild, keep in mind that separate human trials have shown that consuming probiotics (live beneficial bacteria and/or yeasts) can decrease depressive symptoms to a similar degree as Citalopram or Diazepam, two commonly prescribed antidepressants.
So if you’re feeling consistently down or consistently stressed, you might want to reach for some yogurt, sauerkraut, or kimchi—your gut, brain, and body will thank you.