Chances are you’ve heard the buzz around vitamin D. It’s like the superman of the vitamin world that influences everything from your bone health and immune function to the skin, mood, and even your weight.

While health professionals have always steered us away from sitting in the sun, as it turns out, catching some rays can do a lot of good for your body. That is, in moderation. So, while there’s a long list of reasons to get out in the sun, could weight loss be a new incentive?

We’re diving into the link between vitamin D and weight loss and giving you what you need to know before popping back this supplement to whittle away your waistline.

The Basics Of Vitamin D

Vitamin D is a fat-soluble vitamin that the body can synthesize upon exposure to UVB rays from the sun. When UV rays hit your skin, the body synthesizes an inactive form of vitamin D, which is then converted to the active form—1,25(OH)2D—by the liver and kidneys, so it’s ready for the body to use.

Vitamin D plays an essential role in maintaining bone strength and integrity via its ability to regulate calcium and phosphorus levels.

However, its function doesn’t stop there. The vitamin D receptor (VDR) has been found in nearly all cells and tissues in the body, suggesting its role extends far beyond that of calcium metabolism. This includes immune health, mood, cardiovascular function, cognitive health, and, yes, even weight management 1.

While getting out in the sun is one way to get your share of vitamin D, it’s also widely available in food. Although diet isn’t the best way to get vitamin D, consuming oily fish like salmon and sardines, eggs, and mushrooms means you’re getting small amounts.

Obesity And Vitamin D: What’s The Link?

For anyone that’s overweight or obese, there’s another reason to have vitamin D on your radar. Studies suggest that people with higher body masses and adipose tissue have lower vitamin D levels, suggesting that vitamin D may play a role in regulating weight 2.

On top of that, a vitamin D deficiency also increases the risk of type 2 diabetes, cardiovascular diseases, hypertension, and obesity for people already overweight.

The mechanisms behind this link aren’t completely clear, but researchers suggest a few possible reasons 3, 4:

  1. Lower dietary intake
  2. Decreased cutaneous synthesis — a combination of altered behavior limiting sun exposure and reduced synthetic capacity
  3. Reduced intestinal absorption
  4. Altered metabolism
  5. Volumetric dilution in increased volumes of fat, serum, liver, and muscle

In any case, the link between obesity and vitamin D is apparent. Vitamin D receptors (VDRs) have been found in adipocytes (fat cells), which suggests that adipose tissue is responsive to vitamin D 5.

Several mechanisms involving how calcium and vitamin D may influence adiposity and energy balance have been proposed, but studies are still inconclusive.

However, one study suggests that obese individuals generally have low vitamin D status, which may be associated with dysregulation of white adipose tissue 6.

Adipose tissue may be a direct target of vitamin D, as the expression of both the VDR and 25-hydroxyvitamin D 1α-hydroxylase (CYP27B1) genes has been found in human adipocytes.

There’s also evidence suggesting that vitamin D levels influence body fat mass by inhibiting adipogenic transcription factors and lipid accumulation during adipocyte differentiation.

Other evidence points to the role of vitamin D metabolites in influencing adipokine production and the inflammatory response in adipose tissue. As such, a deficiency in vitamin D may compromise the normal metabolic function of adipose tissue.

While low vitamin D isn’t the cause of obesity, research suggests a strong link between the two.

Can Boosting Vitamin D Levels Help You Lose Weight?

There’s no clear evidence that boosting vitamin D levels can facilitate weight loss, but it doesn’t hurt to try—and research is exploring this area more.

A 2014 study published in The American Journal of Clinical Nutrition compared 12 months of vitamin D3 supplementation versus placebo on weight, body composition, insulin, and C-reactive protein (CRP) in postmenopausal women in a weight-loss intervention 6.

218 overweight or obese women aged 50-75 with low vitamin D levels were randomly assigned to a weight-loss + 2000 IU oral vitamin D3 per day or weight loss + daily placebo; the weight-loss group followed a reduced-calorie diet (10% weight loss goal) and 225 minutes/week of moderate-to-vigorous aerobic activity.

Results showed that while the differences weren’t anything to write home about, the women who were able to increase serum vitamin D concentrations to a normal range lost more weight than the women whose vitamin D levels remained low at the end of the study period—as such, keeping vitamin D levels in a healthy range could support more significant weight loss.

Another study looked at the effects of vitamin D supplementation on weight loss in overweight and obese women aged 20–40 years in Isfahan 7. The study used 50 overweight and obese women divided into two groups: the first group received 50,000 IU vitamin D per week for six weeks, while the other group received a placebo.

Various markers were measured before and after the study. At the end of the intervention period, the group supplementing vitamin D saw more significant decreases in weight, waist circumference, and body mass index (BMI) compared to the control group.

There’s quite a large body of research linking vitamin D with obesity, but its role in weight loss is far less clear. Although, some research suggests that vitamin D plays a direct role in suppressing parathyroid hormone (PTH), which promotes fat accumulation in adipose tissue 8.

A deficiency of vitamin D results in an increase in PTH that promotes calcium influx into adipocytes, which ultimately enhances lipogenesis, triggers catecholamines to induce lipolysis and can result in significant fat accumulation and weight gain 9.

Vitamin D Deficiency And Weight

Apart from its role in fat accumulation, vitamin D deficiency may also influence other factors that play a role in weight.

Low levels of vitamin D have been linked to an increased prevalence of depression due to its role in the biosynthesis of serotonin. Many people who are depressed find it challenging to eat healthy, exercise, and practice good lifestyle habits, all of which can add up to weight gain.

A 2017 review published in the Journal of Preventive Medicine & Public Health found that a higher BMI was linked to an increase in depressive days 10; the stigma attached to obesity may trigger feelings of depression.

Another important factor that’s associated with vitamin D levels is sleep. There’s a large body of research showing the link between low vitamin D status and increased sleep disturbances, poorer quality sleep, and reduced sleep duration 11, 12. Studies show that vitamin D receptors are expressed in areas of the brain that regulate the sleep-wake cycle, such as the hypothalamus.

Losing weight can be a challenge in and of itself, but when you’re sleep-deprived, it can be even more challenging to lose the weight and keep it off.

Studies consistently show that people who sleep less than 7 hours a night are more likely to have a higher BMI and develop obesity compared to those who sleep longer 13.

That may be because sleep restriction is associated with increased ghrelin levels, salt retention, and inflammatory markers, along with decreased levels of leptin and insulin sensitivity.

Diets, Supplements, Or Sun: The Ideal Dose For Weight Loss

In most instances, experimental studies looking at the link between vitamin D levels and weight loss rely on supplements rather than food sources or sun exposure. While sun exposure is ideal for increasing vitamin D, supplementation offers a more controlled dosage to boost levels quickly.

When it comes to vitamin D dosage, there’s no magic number. Aiming for a serum concentration equal to or greater than 20ng/mL can help counter the effects of fat storage and may support weight loss in some individuals.

For anyone with a vitamin D deficiency, doses may need to be on the higher end, but avoid mega-dosing without medical supervision.

Because there is no one-size-fits-all model with supplementation, sticking to a general guideline of 32–36 IU per pound (70–80 IU/kg) should be sufficient to maintain adequate levels 14.

On the other hand, if you want to maximize weight loss, adding in a natural fat burner like Burn Lab Pro can help kickstart your metabolic fire to help you lose weight and torch fat.

Final Thoughts

It’s clear that there is a link between vitamin D levels and weight gain or weight loss. If you’re struggling to lose weight or keep the pounds off, a nutrient deficiency could undermine your efforts.

Whether you’re getting it through food, sunshine, or supplementation, getting enough vitamin D can help keep your hormone levels in check and may support your weight loss efforts. In turn, shedding unwanted weight can also help increase vitamin D levels and maximize its help benefits.

If you live in a climate where you don’t have year-round exposure to the sun, setting yourself up with supplemental D3 is to your advantage.

Pure vitamin D3 supplements are widely available, but why not kill two birds with one stone and top up your other daily essentials at the same time?

Performance Lab® NutriGenesis® Multi supplies 17+ essential vitamins and minerals to restore nutrients that may be missing from the diet.

NutriGenesis® is ultramodern nutrition technology unique to Performance Lab®. Multi contains only vitamins and minerals bioengineered with cofactors that boost absorption and maximize benefits so you can unlock your performance potential.


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