Vitamin D is a major factor in why your mood is low during the colder months, especially for those who live in areas that receive less sunlight. If you tend to avoid the sun, wear high amounts of sunscreen, or work at night, you are at even greater risk of vitamin D deficiency. Although there are many dietary sources of vitamin D, the truth is that many of us don’t always eat foods high in this nutrient. According to Healthline, common sources of vitamin D include animal products like eggs, yogurt, and meat, which can cause problems for vegans and strict vegetarians.
A doctor can determine if you’re truly vitamin D deficient by running blood tests (via Mount Sinai). Symptoms of vitamin D deficiency can include anxiety, depression, muscle aches, and hair loss. Some may even notice improvements in their appearance after vitamin D supplementation, such as healthier-looking skin and nails.
Vitamin D is a fat-soluble vitamin, which means you cannot excrete excess vitamin D from your body, and too much can lead to toxicity or serious health problems. According to WebMD, 400 to 800 IU (international units) is enough for most people. However, Harvard Health Publishing reports that the tolerable upper intake level (UL), or the maximum amount that should be consumed daily, for adults is 4,000 IU. For an easy way to get vitamin D without popping pills, try Carlson Super Daily D3 Drops, which provide up to 2,000 IU in just one drop.