Obesity, which is characterized by the buildup of white adipose tissue mass, is a new health problem that is becoming increasingly important. Obesity is linked to several disease outcomes, such as mortality rates and heart disease, diabetes, stroke, and metabolic syndrome. A body mass index of 30 kg/m2 or higher is considered obese according to the World Health Organization.

We frequently find ourselves swamped with countless diets, exercise routines, and supplements promising weight loss results in our search for efficient weight loss methods. Vitamin D is one frequently disregarded element that can be crucial in achieving and maintaining a healthy weight. Vitamin D deficiency has emerged as a potential contributor to obesity and weight gain. While the classic action of vitamin D is more well-known, its non-classic action is less elucidated.

 

In this blog, we’ll look at how vitamin D might impact both weight loss and overall health.

 

WHAT IS VITAMIN D?

The unique feature of vitamin D, also known as calciferol, is that it can be produced by the body as a result of sunlight. It is a fat-soluble vitamin. Vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) are the two main forms of the nutrient.

While vitamin D2 is mostly produced by humans and added to food, vitamin D3 is produced in human skin when ultraviolet B radiation (UVB) enters the skin and is absorbed by 7-dehydrocholesterol. Vitamin D3 is also consumed in the diet through the consumption of animal-based foods. Before undergoing two hydroxylation reactions—the first in the liver to become 25-hydroxyvitamin D, also known as calcidiol, and the second in the kidneys to become the biologically active form, 1,25-dihydroxyvitamin D, or calcitriol—vitamin D, in either its D2 or D3 form, is considered biologically inactive.

 

DIETARY SOURCES OF VITAMIN D

It can occasionally be difficult to fulfil your needs for vitamin D through sunlight, especially if you don't get much sun. A few naturally occurring sources of vitamin D include fatty fish, cod liver oil, fortified dairy products, and egg yolk.

Supplements can be an easy way to make sure you get the vitamin D you need, especially if you live in an area with little sunlight, are older or have a darker skin tone (the high melanin levels may reduce the amount of UVB light absorbed in the skin), or have medical conditions that prevent vitamin D absorption.

 

WHAT IS THE SOURCE OF VITAMIN D USED IN SUPPLEMENTS?

There are supplements for vitamin D2 and vitamin D3 on the market. Vitamin D3 is created by UV irradiating 7-dehydrocholesterol from lanolin derived from sheep wool, while vitamin D2 supplements come from UV irradiating ergosterol in yeast. Lichen is used to produce the vegetarian/vegan vitamin D3 supplement.

 

WHAT IS THE RECOMMENDED INTAKE OF VITAMIN D?

The amount of nutrients that must be consumed on a daily basis in order to meet the needs of all healthy people between the ages of 19 and 70 is 15 mcg or roughly 600 IU.

 

WHY DO THE OBESE HAVE LOW LEVELS OF VITAMIN D?

Despite the fact that obesity has no impact on the skin's capacity to produce vitamin D, obese people frequently lack the vitamin due to a variety of reasons.

1. Obese people spend less time outside in general, which may be due to mobility issues, discomfort from being overweight, or social factors.

2. Compared to individuals of healthy weight, obese people have lower suboptimal levels of 25OHD.

3. The body's metabolism and vitamin D distribution can be impacted by obesity. It might result in modifications to the body's processes for producing, absorbing, and transporting vitamin D.

4. Chronic low-grade inflammation linked to obesity can interfere with the body's absorption of vitamin D.

5. Due to gastrointestinal problems brought on by obesity, obese people may have dietary habits that lack vitamin D-rich foods or may have trouble absorbing dietary vitamin D.

6. The studies came to the conclusion that vitamin D was stored in adipose tissue in obese subjects and was not released when needed, which may have an impact on its bioavailability. Obesity can result in volumetric dilution of vitamin D in larger amounts of adipose tissues, which can lower the levels of this vitamin in the bloodstream. Greater amounts of subcutaneous fat sequester more vitamin D.

 

MECHANISM BY WHICH ADEQUATE LEVELS OF VITAMIN D MAY ASSIST IN WEIGHT LOSS

1. It has been proposed that low vitamin D levels increase adiposity because they increase parathyroid hormone (PTH) secretion and alter adipogenesis. Low vitamin D levels cause increased PTH, which encourages calcium to enter adipocytes and increase lipogenesis while inhibiting catecholamine-induced lipolysis, which results in fat storage and weight gain.

Lowering PTH levels, which reduces the calcium influx into adipocytes and boosts lipolysis, will result in adequate vitamin D levels. It has been proposed that decreasing PTH levels through an increase in vitamin D levels could cause weight loss through lipolysis and thermogenesis mediated by the sympathetic nervous system.

2. By influencing hormones like leptin and ghrelin, vitamin D may have an impact on hunger and satiety. While ghrelin increases appetite, leptin signals fullness. A balanced appetite can be maintained by adequate vitamin D levels, which may help prevent overeating. Low vitamin D levels are linked to low leptin levels, which can cause an increase in appetite. A seasonal variation in vitamin D levels may be the cause of cravings for foods high in calories that some people have during the winter.

3. Lipid metabolism, which affects how the body stores and burns fat, is influenced by vitamin D. According to some studies, the body can more efficiently use stored fat for energy when vitamin D levels are adequate.

4. In addition to regulating lipolysis, vitamin D also enhances insulin signaling pathways (through its role in calcium regulation and by supporting the healthy operation of beta cells). Improved insulin sensitivity can result in better blood sugar control and less fat storage, which facilitates weight management.

5. Due to its anti-inflammatory properties, vitamin D may help with the dysfunction of adipose tissue. Reducing inflammation is thought to enhance insulin sensitivity and combat insulin resistance.

6. Sufficient vitamin D levels can support the maintenance of a healthy range of serotonin, can increase levels of serotonin (a neurotransmitter that regulates mood and appetite), and may contribute to appetite control and increase feelings of satiety after meals. Increased appetite and cravings for foods high in carbohydrates are linked to low levels of appetite.

Despite solid evidence concerning consequence of vitamin D, a general disregard of vitamin D deficiency is seen globally. Vitamin D supplements are the simple, effective and inexpensive means to available to correct the vitamin D deficiency.

 

Reference:

https://www.ncbi.nlm.nih.gov/books/NBK5

https://www.ncbi.nlm.nih.gov/pmc/articles

https://www.ncbi.nlm.nih.gov/pmc/articles