As part of Women’s Health Week, we’re looking at the link between the gut and the health concerns that are most commonly faced by women. Today, we’re focussing on our Generation Y and Millennial female friends, with this content developed by Paul Sims from The Healthy Grain.
Females are over-represented in a number of morbidity and mortality statistics, including the expected obstetric and gynaecological related conditions; this includes depression and gastrointestinal upsets such as irritable bowel syndrome (IBS) and bloating, and skin conditions.
There is an established link between diet and depression. Traditional diets such as the Mediterranean or Norwegian or Japanese are recommended as are diets rich in legumes, fruit and vegetables and wholegrains for reducing the depressive symptoms. Not surprisingly, studies have shown that dietary fibre consumption is inversely related with depressive symptoms; and that prebiotics and probiotics are linked to improved mental function (Ansari et al).
There is an established gut-brain axis whereby the gut can influence the brain and vice versa. There are a variety of ways this can work involving the nervous system or neurotransmitters such as serotonin, hormones and the immune system. The mechanism linking dietary fibre is not certain but may involve alterations in the permeability of the gut wall, changes in the gut microbiome, changes in inflammation or increased production of neurotransmitters.
There is also an association between depression and an altered abundance of different bacterial genera in the gut microbiome. The question is whether this is a consequence of depression (for example dietary change due to depression) or whether the change is part of the cause of the depression, is to be resolved. There is evidence that stress itself alters the gut microbiome.
Scientists are paying more attention to the inflammatory response. For example, its role in coronavirus infections, and are linking altered inflammatory responses to many diseases such as depression as well as obesity, diabetes and heart disease. It may well be possible that an altered inflammatory process is involved in the development of all three latter diseases.
A few studies have found that people who eat high fibre diets have lower C-reactive protein (CRP) in their blood. CRP is a marker of inflammation linked to rheumatoid arthritis, heart disease and diabetes. However, it is possible that depression preceded the change in CRP and other inflammatory markers suggesting that the beneficial effect of dietary fibre on depressive symptoms may have another mechanism.
Studies have shown that consuming prebiotics and probiotics can have a positive effect on various measures of skin health. A small number of studies have shown probiotics improving factors such as skin moisture, decreasing the depth of wrinkles and increasing elasticity. It has been proposed that the various beneficial effects may be mediated through an anti-inflammatory route.
Some Korean women attribute their excellent complexion to a number of factors including the consumption of kim chi, a fermented cabbage. Trials have shown a variety of beneficial health effects of kim chi consumption, such as reducing coronary heart disease risk factors but trials involving skin health are limited at this stage.
Dietary fibre supplementation has been found to be beneficial in constipation predominant IBS (although larger and more rigorous trials are needed). (Rao et al). Unlike the indirect links between dietary fibre consumption, depression and skin health, this effect may be direct.
There is a lot to be learnt about the mechanism by which diet influences these diseases in which females are over-represented. However, there is strong evidence that higher intakes of dietary fibre may reduce the risk of certain of these diseases.
Intended as general advice only. Consult your health care provider to discuss any specific concerns.
F. Ansari et al. The Effects of Probiotics and Prebiotics on Mental Disorders: A Review on Depression, Anxiety, Alzheimer and Autism Spectrum Disorders (2020) Current Pharmaceutical Biotechnology v21 p555-565.
Rao S.S.C. et al. Alimentary Pharmacology and Therapeutics (2015) – Systematic review: dietary fibre and FODMAP restricted diet in the management of constipation and irritable bowel syndrome.