Don't Let the Darkness Loom Over Your Health: Everything You Need to Know About the Sunshine Vitamin

 Written By: Dylan Moffatt; SLU Dietetic Intern

As the clocks fall back into standard time, we are officially into the season of cozy sweaters, shorter days, and the undeniable craving for sunshine again, though some people may like the darkness. We are on standard time until March 9th, 2025, when we spring forward to Daylight Savings Time. One way to remember which way the clocks go is in the Fall we fall back an hour; in the spring we spring forward an hour. So as our daylight slowly falls away, it’s time to talk about what we all love, the sunshine and the incredible nutrient it brings us Vitamin D!

Sunshine does not just lift our spirits or warm our faces on a winter day but its also our personal health ally, helping our body produce Vitamin D, nicknamed the sunshine vitamin, rightfully so. This powerful vitamin is a key role in our body’s quest to maintain health. Although the sun is all around us, just under half of all Americans are deficient (42%). Let’s bundle up and let the sunshine some light on Vitamin D and reveal why it is so important.

Why is vitamin D important?

Vitamin D promotes calcium absorption in the gut and helps maintain adequate levels of minerals to enable bone health and prevent low levels of calcium, which may cause cramps or spasms. Vitamin D is needed for bone growth and bone remodeling throughout our lifespan and without it our strong bones can begin to weaken, become brittle, or misshape. This vitamin also plays a role in reducing inflammation, cell growth, neuromuscular and immune function and glucose metabolism. It also may help improve your mood as the dark winter approaches and the winter blues come hollowing in.

What are symptoms of deficiency?

There are many symptoms to vitamin D deficiency and its always best to consult a doctor to determine if you are at risk and should be tested. A doctor can also prescribe the right dosage based on your test results. It should be noted that symptoms can be subtle and could also be part of a different problem. Some symptoms may include frequent illness/infections, fatigue, tiredness, bone/back pain, impaired wound healing, and bone loss. It’s best to consult a doctor to determine if your symptoms may be from a vitamin D deficiency.

What is the difference between Vitamin D2 & D3?

The only difference between them is in their chemical structure, and both can be well absorbed into the small intestine. Vitamin D is a fat-soluble vitamin which means it absorbs well when fat is present in the small intestine, though some of it still absorbs when no fat is present. There is no difference in absorption between the two, the only main difference is D3 usually is found in animals and D2 is usually found in plants.

How much do I need?

Below is a table based on age and there is no difference between sexes. Vitamin D is also required on all food labels under the nutrition facts, so I can easily be found at the bottom. Fun fact: Vitamin D, Calcium, Iron, and Potassium are the nutrients considered mandatory for every food label.

How do I get Vitamin D?

The best food sources that contain vitamin D are trout, salmon, tuna and mackerel. Animals’ diet affects how much vitamin D is found in their meat. Other sources also include beef liver, egg yolks, and cheese, though they have small amounts. Some mushrooms contain vitamin D as well, and when exposed to UV light it increases their levels of the vitamin just like us! Fortified foods are where most Americans get vitamin D. The milk supply usually has vitamin D added as it helps with calcium absorption as well. Other products that are fortified include breakfast cereals, some orange juices, yogurt, and other dairy products. From the sun it is best during midday during the summer, making it the smallest amount of time needed to have enough vitamin D production, it can take anywhere between 10-30 minutes to have enough exposure. Too much sun can cause damage to the skin and have serious consequences. The more skin that is exposed to sunlight, the greater the exposure in less time, and it is best not to use sunscreen as it will affect the UV rays absorbing into the skin. It is best to limit overall sun exposure due to risks like sunburn, eye damage, aging skin, heat stroke, and skin cancer. When in the winter months it is best to either consume foods which contain vitamin D or are fortified with it. You can always ask your doctor if a vitamin D supplement is right for you in the winter months.

What are the top sources of Vitamin D?

3 oz of Trout provides 16.2 mcg

3 ounces of sockeye salmon provides 14.2 mcg

1 cup of fortified 2% milk contains 2.9 mcg

1 serving of fortified breakfast cereal contains 2.0 mcg

1 large egg provides 1.1 mcg

Can I overdo it on Vitamin D?

Like overloading hot chocolate with too many marshmallows, too much vitamin D can cause issues. It is best to stick to recommended amounts or talk to your healthcare provider.

As you embrace the colder months with blankets and warmth do not let the winter months dim out your vitamin D. You can soak in the limited sun or enjoy a bowl of cereal or OJ remember the winter won’t last forever. The winter darkest may be upon us but that does not mean our health has to enter a dark period as well.

References:

1. Raman R. How to safely get vitamin D from the sun. Healthline. April 4, 2023. Accessed November 10, 2024. https://www.healthline.com/nutrition/vitamin-d-from-sun.

2. Wartenbery L, Armstrong M. Vitamin D deficiency: Symptoms, treatments, and causes. Healthline. January 19, 2024. Accessed November 10, 2024. https://www.healthline.com/nutrition/vitamin-d-deficiency-symptoms#seeing-a-doctor.

3. Office of dietary supplements - vitamin D. NIH Office of Dietary Supplements. July 26, 2024. Accessed November 10, 2024. https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/