Most Americans Are Deficient In This Essential Weight-Loss Vitamin

 There are many things you can do to prepare for your weight loss journey: stock your pantry with healthy foods, meal prep, and write down your intentions. But there's one additional, oft-overlooked thing to consider before you start losing fat: analyzing your nutrient intake. In particular, it's important to find out if you're suffering from any vitamin or mineral deficiencies that may hinder your weight loss progress. If you want to lose weight, you should check to see if you have a vitamin D deficiency. 

There has been much talk recently about vitamin D's connection to immune health—and COVID, in particular—but there's another little-known benefit of vitamin D: weight regulation. The only problem? Anywhere between 40% to 70% of Americans are deficient in vitamin D.

Vitamin D is essential for bone and immune health, mood regulation, and it may help with muscle strength, protecting against cancer and type 2 diabetes, and weight maintenance.

How is vitamin D linked to weight regulation?

As it relates to weight loss, a recent meta-analysis found that the prevalence of vitamin D deficiency can be 35% higher in obese subjects and 24% higher in those who are overweight compared to those with "normal" body mass index (BMI).  

Another meta-analysis supports this, finding that those with lower vitamin D levels had a higher likelihood of an increased BMI in both diabetic and non-diabetic patients. And a Diabetes study found that participants with lower levels of vitamin D were more likely to have larger waist circumferences and higher levels of fat—even in lean individuals with healthy BMIs.

There isn't enough evidence to discern whether lower vitamin D is a consequence of weight gain or a cause of weight gain. Experts have several theories about the connection between vitamin D and weight.

One is that excess body fat may store vitamin D, so those with a higher content may have more space to store this vitamin D, resulting in a deficiency. Another is that vitamin D may help to prevent cells from turning into fat cells; thus, without the fat-stopping vitamin D, it may cause more fat cells to form.

Researchers are looking to design clinical trials to find whether providing vitamin D supplementation to overweight and obese individuals can lower BMI.

What to do if you're not getting enough vitamin D.

If you believe you have a vitamin D deficiency (and even if you don't), it's best to consult your doctor or registered dietitian to run some tests.

In the meantime, there are some things you can do to increase your vitamin D levels in a safe way:

Ultraviolet light from the sun helps people form vitamin D in the skin (this is where 80-90% of your vitamin D comes from), so spending time outdoors can improve your vitamin D levels. You can also get the nutrient naturally from foods like fatty fishes, mushrooms, egg yolks, and liver. There are also some foods that are fortified with vitamin D, like milk and yogurt.