Study links women’s happiness to digestive health

A recent study suggests that your digestive health has more to do with your mood than you might realize.

In the study, conducted by Brigham and Women’s Hospital and the Harvard T.H. Chan School of Public Health, women who reported feeling happier had lower levels of Firmicutes bacterium CAG 94 and Ruminococcaceae bacterium D16 in stool samples. Women who reported feeling more negatively had more of those bacteria.

The research was based on 206 white women from the ages of 49 to 67, so it’s not a huge study, nor a particularly diverse one, but one that we can look into further.

But these findings aren’t too surprising to experts, who agree that good gut health is linked to better mental health.

The study’s sample obviously has a lot in common, but the findings may be universal to a degree, experts agreed.

“Since menopause can last seven to 14 years, starting around ages 45 to 55, it is possible that some of these women also experienced mood disruptions related to either their cycle or hormones driving menopause,” Dr. Noelle Patno says. “On the other hand, an earlier study including both men and women also suggested that the gut microbiome may be associated with mood changes as well. In general, symptoms of abdominal pain and irregularity do often coincide with anxious and depressive symptoms.”

“There is definitely a clear link between women’s emotional health and their gut health, with our bodies literally having a direct connection via the vagus nerve to send messages between the gut and the brain,” adds Kara Landau, a registered dietitian at Gut Feeling Consultancy. “It is known that when you have poor gut health, or dysbiosis (an imbalance of good to bad bacteria in your gut), inflammatory molecules are released by the gut bacteria, and it is also widely accepted that inflammation is linked to anxiety and depression.”

According to Landau, the link between stress and gut health may be bidirectional, making gut health even more important to emotional health overall and vice versa.

“When someone is feeling stressed, this can also lead to negative impacts on the gut,” she says. “Therefore, findings ways to manage stress, and to nourish the gut, both play a role in improving mental well-being and overall gut health.”

Which foods can help gut health?

You can adjust your diet in ways that may benefit your emotional well-being, experts say. Here’s what they recommend.

Fermented foods: These can include cottage cheese (dry curd), kefir, kimchi, kombucha, miso, pickles (in salt brine, not vinegar), sauerkraut, tempeh and plain yogurt.

Dr. Sean Byers says, “A healthy gut microbiome is associated with better digestion, immunological function and mental health, and fermented foods include live cultures of beneficial bacteria that can help support this microbiome. In addition, eating fermented foods has been shown to decrease inflammation in the digestive tract and the body, which may lead to enhanced health and well-being.”

Whole foods with prebiotic fiber: Chances are you aren’t eating enough of the fiber-rich foods that can improve your emotional and gut health, says Dr. Vincent Pedre, author of “The Gut Smart Protocol.”

“Most women only get about 10 to 20 grams of fiber in their diet, but if you want to create a positive impact on your gut health to improve your brain health, aim for at least 40 grams daily,” Pedre advises. “This is the equivalent of six to eight servings per day of fiber-rich vegetables and fruit.”

Whole foods rich in prebiotic fiber include apples, asparagus, bananas, barley, chicory root, dandelion greens, flaxseed, garlic, leeks, oats, onions, seaweed and wheat bran.

“Supporting a generally healthy microbiome starts with reducing foods that selectively feed ‘bad’ bacteria (like added sugars), and aiming to include soluble fibers that ‘good’ bacteria love to eat,” Patno says. “Gut bacteria can metabolize fiber to produce short-chain fatty acids, which are also thought to support the brain. Boosting the health of your gut microbiome by choosing healthier carbohydrate sources could potentially contribute to better emotional health as well.”

Foods high in tryptophan: Patno says that the same chemical we all blame for our Thanksgiving food comas (as opposed to our actual overindulging) is actually great for gut health. Some good sources of tryptophan include apples, bananas, cheese, chicken, oats, peanuts, prunes, turkey, tuna, whole milk and whole wheat bread.

Patno explains that tryptophan is “the starting material our cells use to make the neurotransmitter serotonin. When serotonin is made in the brain, it is responsible for mood and emotional regulation.”

There’s an added layer, she says, to its gut-mental health connection: “When serotonin is made by cells in the lining of the gut, it acts in gut motility, to help keep you ‘regular.’ ”

Foods rich in healthy fats: Patno likes the Mediterranean diet for its richness not just in whole foods and fiber, but also in healthy fats.

“Insufficient quantities of healthy fats or fiber could disrupt the gut microbiome and gut motility as well as dysregulate mood,” she says.

You can find healthy fats in almonds, avocados, Brazil nuts, cheese, chia seeds, eggs, flaxseed, herring, macadamia nuts, mackerel, olives, salmon, sardines, tofu, trout, tuna, unsweetened yogurt and walnuts.

Which foods may harm gut health?

While whole foods are fabulous for gut health and possibly correlated with emotional well-being, a lot of the foods we turn to for comfort may be doing more harm than good. These include candy, ice cream, instant noodles, packaged snacks, pizza, soft drinks, and yogurt with artificial sweeteners.

“Processed and high-sugar foods, such as refined grains, sweets and sugary drinks, can have a negative impact on both gut health and emotional health,” says Barbara Kovalenko, a registered dietitian and nutrition consultant at Lasta. “These foods can disrupt the balance of healthy gut bacteria and may contribute to inflammation in the body, which has been linked to depression and other mood disorders.”