Every week, we’re bringing you a roundup of the latest health and wellness news to hit the wire. This week, we look at how changes in your gut can improve your mental well-being, how exercising fasted appears to burn more fat, and why the high glucose of obesity can wear down the circadian clock, leading to cardiovascular disease.
A crash course in “psychobiotics”
A growing body of research suggests that if the microbes in your gut are happy, you’ll be happy, too, a connection often referred to as the “microbiome-gut-brain axis.”
This year, a large review of studies, covered by BBC’s Science Focus, found that probiotics yielded a small but significant effect in reducing anxiety and depression. A smaller study published in the journal Translational Psychiatry found that administering a Bifidobacterium probiotic into the guts of healthy volunteers reduced feelings of stress and improved their memory. And another trial by researchers in Baltimore found that giving people probiotics to people discharged from the hospital following a manic phase of bipolar disorder significantly reduced their chances of being rehospitalized.
Moreover, patterns of anxiety and depression are linked with certain patterns of gut microbes. An analysis of data from more than 1,000 people in Belgium and Holland found that the presence of some types of gut bacteria was consistently associated with a higher quality of life while the absence of these microbes was linked to depression.
Findings such as these are giving rise to a new class of probiotic and prebiotic medicines known as “psychobiotics,” which scientists hope can be used as a treatment for milder forms of depression and anxiety.
So how is your gut telling your brain how to feel?
- Chemicals produced by bacteria may influence signals sent by nerve endings in the digestive system to the brain via the vagus nerve.
- Gut bacteria such as Bifidobacteriaalso produce the amino acid tryptophan, which is an important building block of serotonin, a brain chemical known to influence mood.
- Lastly, scientists believe that bacteria could be influencing gene expression in the brain. When microbes in the gut digest fiber, short-chain fatty acids are released as a byproduct. These acids could be traveling through the bloodstream to the brain, where they act as epigenetic modulators, reprogramming some brain functions and influencing mood.
Another reason to squeeze that run in before breakfast
Exercising before breakfast in the morning can help people burn more fat and better control their blood sugar, according to a new study published this month in The Journal of Clinical Endocrinology & Metabolism and covered by Healthline.
In a six-week study, researchers from the University of Bath and the University of Birmingham in the U.K. studied dozens of men who were overweight or obese who were sedentary, before starting a cycling exercise program.
Those who exercised before breakfast after fasting overnight burned twice the amount of fat than those who exercised after their morning meal. And the pre-breakfast group had lower insulin levels during exercise, which can help lower the risk of conditions such as heart disease and diabetes.
Researchers say it is these lower levels of insulin that drive fat loss as exercisers end up using more of their own fat tissue as fuel.
While there were no significant differences in weight loss between the two groups, there are important long-term payoffs in insulin sensitivity and muscle adaptation. And it provides helpful exercise guidance for those with diabetes or at risk of it.
How high blood sugar disrupts your body’s circadian clock
For more interesting reading on how high glucose levels in obesity can drive cardiovascular disease, turn to this article in Science Magazine, which explains how high blood sugar messes with the circadian clocks inside our cells that regulate the timing of body functions, switching genes on and off and prepping us to wind down for sleep or rally in the morning.
Scientists, interviewed for the story, are working on a grant from the National Institutes of Health to enable the use of intermittent fasting and developing a category of clock repair drugs to help solve this problem and improve cardiovascular function.
The problem appears to be one of timing. Proper signaling by the cells requires a peak and trough period, and constant overstimulation with glucose has the body instead trying to turn the clocks off.
Photo credit: AzmanL, Getty Images