A diet that’s high in fat may not be enough to cause the heart-harming effects associated with metabolic syndrome — you may also need to suffer from vitamin D deficiency for the ill effects to take hold.
That’s what a new study from researchers at Cedars-Sinai Medical Center and China’s Sichuan University are reporting in the journal Frontiers in Physiology. A vitamin D infusion, which the researchers have so far tested in mice, proved to significantly lessen the symptoms of metabolic syndrome in the rodents.
Metabolic syndrome refers to various risk factors, including abdominal fat and elevated blood sugar, that can increase the risk of heart disease, diabetes and stroke. National health estimates say that more than one-third of U.S. adults are affected by metabolic syndrome.
If the results of the current study can be translated to humans, the medical community would have a powerful tool to help combat metabolic syndrome and its risk factors.
How Vitamin D Improves Gut Health
The researchers believe that extra vitamin D helps to improve gut health by replenishing good bacteria. The complex interplay between diet, gut bacteria and vitamin D levels is not entirely understood, but the results of the study reveal important effects of vitamin D consumption.
“Unbalanced gut microbiota (dysbiosis) … may lead to alteration of immunity and increased risk of diverse diseases, including type 2 diabetes and obesity,” write the researchers.
They also note the deleterious effects of vitamin D deficiency, which they say “affects 30-60 percent of population worldwide, and is increasingly found in association with many diseases including autoimmune diseases, hepatitis and cancer,” according to the study.
Previous findings agree. “Research over the past decade suggests that vitamin D plays a much broader disease-fighting role than once thought,” states a Harvard School of Public Health fact sheet.
The current study provides a key new insight into the benefits of vitamin D consumption. “Based on this study, we believe that keeping vitamin D levels high, either through sun exposure, diet or supplementation, is beneficial for prevention and treatment of metabolic syndrome,” said study author Stephen Pandol, M.D., of Cedars-Sinai Medical Center, in a statement.
In the present study, the researchers studied how extra vitamin D affected mice given a high-fat diet. After beefing up the animals with vitamin D, they found that mice had improved metabolic health, including less insulin resistance when compared to a control group that didn’t receive vitamin D supplements.
Generally speaking, the vitamin D supplements improved intestinal health in the mice by augmenting the signaling between intestinal cells and good bacteria. Importantly, vitamin D has shown to rebalance gut bacteria, which can reduce fatty liver and lessen the impact of metabolic syndrome overall.
“A sufficient dietary vitamin D supplement can partially but significantly antagonize metabolic syndrome caused by high fat diet in mice,” said Pandol. “These are amounts equivalent to the dietary recommendations for humans.”
The researchers’ next step is to confirm the findings in humans, said co-author Yuan-Ping Han of Sichuan University in China. “We are planning a clinical study to confirm the link of vitamin D deficiency with gut bacteria disruption, and its association with metabolic syndrome.”