What does vitamin D insufficiency have to do with belly fat?

Research by Brazilian and British scientists shows that fat cells “kidnap” nutrients from the blood; lack of the substance can lead to problems in the immune system

Agência FAPESP – A study conducted by researchers from the Federal University of São Carlos (UFSAuto), in collaboration with University College London (UK), demonstrated, for the first time, that the accumulation of abdominal fat is a risk factor for insufficiency and deficiency of vitamin D in people over the age of 50. Considered a hormone, vitamin D performs various functions in the body and its deficiency can lead to various problems, such as the absorption of calcium and phosphorus and the functioning of the immune system.

“Both abdominal obesity and vitamin D insufficiency and deficiency are prevalent problems in the elderly population. However, with this study we demonstrate that it is abdominal fat that increases the risk of vitamin D insufficiency and deficiency, not just the relationship reverse, as some studies had already demonstrated. We do not exclude that vitamin D leads to obesity, but only by demonstrating that the accumulation of abdominal fat is also a pathway for the lack of this vitamin,” says Tiago da Silva Alexandre, professor of Gerontology at UFSCar and author of the study published in the journal Nutrients.

The work involved analyzing a database of 2,459 Britons over the age of 50 who were followed up over four years. The research participants are part of the English Longitudinal Study of Aging (ELSA) project, a longitudinal study conducted in England which collects multidisciplinary data from a representative sample of the English population. The analysis was supported by FAPESP.

To test the correlation between the two factors, the researchers selected ELSA project participants who were over 50 years old and had normal vitamin D levels (above 50 nmol/L). The participants were divided into two groups: one with people with little abdominal fat and the other with accumulation of fat in the abdomen (waist circumference greater than 102 cm for men and greater than 88 cm for women).

“When assessing the vitamin D score of these individuals four years after the first data collection, we found that those with abdominal obesity had a 36% increased risk of developing insufficiency and a 64% increased risk of deficiency.” of vitamin D, compared to the group that didn’t have abdominal obesity,” says Alexandre.

In the study, people considered to have vitamin D insufficiency had rates between 30 and 50 nmol/L of the substance in their bloodstream, while the deficiency was configured for those who had less than 30 nmol/L of vitamin D.

According to Alexandre, previous research had already linked a lack of vitamin D with the development of obesity. “However, these studies based on body measurement index (BMI) measurements, using data on weight and height, provide a global analysis of obesity and are very inaccurate. However, the question that remains is how many countries with high or low solar incidence have a very high prevalence of vitamin D deficiency. The answer is because there is a high prevalence of obesity,” says the researcher.

Obtaining vitamin D is mainly through sunlight. This is because it is in the deepest layers of the skin that a precursor substance of vitamin D is stored. When the skin is exposed to the sun, its structure changes and, through various metabolic processes, vitamin D is converted into its active form, which it then circulates throughout the body and performs various functions.

Alexandre explains that, throughout the aging process, changes in body composition are natural, such as increased accumulation of fat in the abdominal region. Furthermore, it is common to reduce the thickness of the skin and, consequently, a lower availability of the precursor substance of vitamin D in the epidermis, as well as a lower synthesis capacity of the active form of this vitamin.

“For this reason, in our study, we used measurements of waist circumference, a practical and accessible measurement that checks for fat accumulation in the abdomen and is more accurate than BMI, for example,” she says.

Another evidenced change with aging is the decrease of vitamin D receptors in body tissues, which makes it difficult to capture the circulating vitamin in the body. But, the study points out, the accumulation of abdominal fat plays an important role in the “sequestration” of vitamin D circulating in the bloodstream.

“When we analyze the fat cells of these people, it can be seen that the vitamin D enzymes are low. This happens because a vitamin D receptor (VDR) begins to capture the vitamin D that is in the bloodstream. This occurs as a way to compensate for the low level of enzymes in fat cells,” says Thais Barros Pereira da Silva, a science initiation student and first author of the study.

According to her, it is as if the adipose tissue “kidnapped” the nutrient. “Which means there is less bioavailability of vitamin D in blood tests, as we see. It is this process that will lead to insufficiency or even deficiency of vitamin D,” she adds.

Alexandre points out that the study reinforces the need for public policies to prevent and address both obesity and vitamin D deficiency in later life.

The job Is abdominal obesity a risk factor for the incidence of vitamin D insufficiency and deficiency in the elderly? Evidence from the ELSA study you can read it here.

Source: Terra

Ben

Ben Stock is a lifestyle journalist and author at Gossipify. He writes about topics such as health, wellness, travel, food and home decor. He provides practical advice and inspiration to improve well-being, keeps readers up to date with latest lifestyle news and trends, known for his engaging writing style, in-depth analysis and unique perspectives.