There may be an association between vitamin D deficiency and a higher body weight. However, it’s not clear whether vitamin D supplementation may help prevent or reduce weight gain.
Vitamin D is crucial for the health of your bones, brain, and immune system. When vitamin D levels are severely or chronically low, symptoms like fatigue or bone weakening can develop.
If you think you may have a vitamin D deficiency, a healthcare professional can help you measure your levels and recommend next steps.
Though research shows there may be a link between vitamin D levels and weight, the relationship isn’t exactly clear. There’s still some debate over whether vitamin D deficiency causes weight gain or is a result of weight gain.
According to a 2019 research review, there’s some evidence to support both theories. Some of the studies included in the review suggest that vitamin D inhibits the production of fat cells, so low vitamin D levels allow for more fat cell production.
The same research review notes that a higher body weight may also lead to vitamin D deficiency because people with obesity have more adipose (fat) tissue. Vitamin D is stored in adipose tissue, so people with obesity may need to get more vitamin D to maintain the same vitamin D levels as people without obesity.
Another 2024 study suggests that the bodies of people with obesity may not convert sunlight to vitamin D as efficiently as people with lower body weights.
Ultimately, there may be a bidirectional relationship between vitamin D levels and weight, with changes in one contributing to changes in the other.
Despite the potential association between vitamin D levels and weight, it’s not clear whether getting more vitamin D will significantly affect weight.
Some research does suggest a positive effect of vitamin D supplementation. For example, a small 2018 study found that 6 weeks of weekly supplementation with 50,000 international units (IU) of vitamin D led to significant decreases in weight, waist and hip circumference, and body mass index (BMI).
However, a
The relationship between vitamin D levels and weight is complex and requires further research.
Regardless of its impact on weight, it’s still important to get enough vitamin D to support overall health.
There are a few lifestyle changes you can make to boost your vitamin D levels.
One way is to get more sunlight. The body makes vitamin D after sunlight exposure. It’s important to stay safe, though — make sure to apply sunscreen and wear protective clothing.
You can also try including more foods high in vitamin D in your diet. Some animal-based foods, like egg yolks and fatty fish, are good sources of vitamin D. Plant-based options include mushrooms and fortified cereals or plant milks.
You can also try taking supplements if your doctor recommends it. The recommended daily amount is
If you suspect you may have low vitamin D levels, your doctor can order a blood test to rule out a deficiency.
Depending on your results, your doctor may recommend some combination of supplements, dietary adjustments, and sunlight exposure. They can also recommend next steps if you’re concerned about weight gain.
Studies suggest a possible relationship between vitamin D deficiency and weight gain, but the exact nature of that relationship isn’t fully understood. Additionally, research hasn’t definitively shown that getting more vitamin D will lead to weight loss.
If you want to get your vitamin D levels tested, ask your doctor about scheduling a blood test.