Vitamin D in obesity

Introduction
There are multiple nutrients, each of them contributing in the right portion to make up for the perfect composure of the body. Vitamin D or Calciferol is one of those essential nutrients that many bodily functions depend upon. From digesting food to taking care of the bones, the relevance of this sunshine vitamin ascertains to be inevitable. However, numerous factors affect vitamin D absorption and fluctuate its levels in the body. Also, several physical states such as obesity play a role in altering vitamin D levels.

Obesity is nothing but an accumulation of abnormal or excess fat in the body, which is more of a health issue than being a mere physical condition. It is found that multiple diseases could initiate if a person is suffering from obesity. Studies by researchers have revealed that vitamin D deficiency is connected with obesity. Also, scientists have found an inverse relationship between vitamin D levels and obesity.
Let’s look at how obesity influences vitamin D and vice versa.

Relationship between obesity and vitamin D deficiency

It is known that vitamin D is a fat-soluble vitamin, which means that the vitamin D molecules are held by the body’s fat cells. The level of Vitamin D in the body is determined by the concentration of 25-hydroxyvitamin D in the serum. Obese individuals have a lower concentration of 25-hydroxyvitamin D in serum and a high BMI index.
Below are some of the different theoretical justifications that explain the connection between obesity and vitamin D levels in the body.

• More storage capacity
  There are different sources of vitamin D available such as sunshine, food, and supplements. Irrespective of the source of vitamin D, the molecules of this vitamin are taken up by the adipose tissues. In obese individuals, the adipocytes or the adipose tissues are more in quantity. This indicates that more spaces are available for the vitamin D molecules to dwell. Obesity, in a way, generates more storage capacity for vitamin D, and thus fewer molecules get available in blood circulation and for their respective uses in the body.
• Less physical activity
  Several hypotheses suggest that less physical activity of an individual could trigger obesity and the subsequent vitamin D deficiency. This, in a way, also prevents one from being involved in outdoor activities and getting sun exposure. Also, fewer physical activities discourage one from burning calories, contributing to more fat and eventually to less vitamin D levels in the body.
• Influence of weather
  As per one study, it is found that the adaptive winter action (lethargy, laziness, fatigue) relates to obesity. The limited sunlight during the winter season leads to procrastination towards physical activity and finally elevating the body’s fat cells. Less sunlight combined with the increase in adipocytes could contribute well to decreasing vitamin D levels in the body.

Could vitamin D help in treating obesity?
There have been theories explaining the connection between vitamin D sufficiency and its assistance in treating obesity. Also, few studies have unveiled that vitamin D could help weight loss. Below are some logical assumptions showing the usefulness of vitamin D in weight loss.

• Reducing adipogenesis
  Studies have shown that Vitamin D impedes the formation
  of new fat cells in the body. This is because it reduces the rate of abiogenesis, a process by which the new fat cells are formed in the body. Also, it suppresses the
  accumulation of fat cells or adipocytes; thus, there is less fat deposition in
  the body.
• Level of enzymes
  Vitamin D enters in its inactive form inside the human body. Some enzymes in the body are required to convert the absorbed vitamin D
  into its active form. The activation is needed to make vitamin D available for bodily functions, without which it has no relevance in the body. It is here to note that few studies suggest a difference found in the levels of these enzymes between obese and non-obese individuals.
• Regulating serotonin
  Serotonin is a neurotransmitter that is found to regulate
  mood and sleep patterns. Vitamin D contributes to increasing serotonin levels in the bloodstream, promoting mood stability, which is required to maintain a stable weight. Also, serotonin is known for controlling the appetite of an individual and increasing satiety over food intake so that there are fewer chances of overeating. Thus, this helps one consume fewer calories and assist in weight loss.
• Regulating testosterone
  Research on Vitamin D has found a link between vitamin D
  and testosterone hormone. Vitamin D is found to increase the levels of
  testosterone in males. Testosterone is known for reducing body fat and
  continuing the process of weight loss for longer. Moreover, high testosterone levels in males promote long-term weight loss and kick off obesity.
• High energy expenditure
  Some studies claim that vitamin D can increase the uncoupling of oxidative phosphorylation in the body’s fatty tissues. Also, vitamin D could affect free fatty acids from the adipose tissues. These could
  sum up and contribute to the increase in the energy expenditure of the
  adipocytes of the body. This implies that vitamin D helps burn more calories, which helps prevent or overcome obesity.

Underlying contradictions
Though there have been numerous studies showing the effectiveness of vitamin D in treating obesity or the influence of vitamin D levels on body fat, there are hardly any shreds of evidence that could firmly back such studies.

People should understand that it is essential to maintain an ideal weight for sustaining a healthy life. Obesity does not just create a deficiency of vitamin D. However; also it can be responsible for inviting a variety of diseases, such as cardiovascular diseases, hypertension, risk of type 2 diabetes, and so on. Further, a vitamin D deficiency could add more to the health issues and make one face the worst scenario. Thus, it would be better to establish a balance to nurture themselves well and avoid an unfavorable health crisis.

References:

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