Whether you live in a part of the world that’s a winter wonderland for a portion of the year or you get year-round rays of sunshine, statistics say you’re still more likely to be deficient in vitamin D that not.“Out of 100 patients, I’d say 80 are significantly deficient,” integrative physician and internist Svetlana Kogan, MD, previously told Well+Good.

This is unfortunate news, as vitamin D is a powerhouse nutrient that’s a key part of so many bodily functions—think reproductive health, mental health, bone health, and even the strength of your immune system. “It’s essential that we are equipped with an adequate in order for all these systems to be running efficiently and effectively in place,” says Tracy Lockwood-Beckerman, RD. Additionally, deficiency can cause things like loss of bone density, poor mood, and exhaustion. Experts have gone so far as to say that vitamin D deficiency is an ignored epidemic and it only gets worse as we age.

“In fact, vitamin D deficiency increases dramatically as you age,” says functional medicine professional and naturopathic doctor Lana Olivia, ND, LAc, aka Dr. Lana. “The older you are the more brittle your bones become, the less physical activity you engage in and, usually, the less sunlight you receive on a daily basis, all of these things play into vitamin D levels. Elderly people also benefit tremendously from the immune boosting benefits of vitamin D, so it’s very important that they monitor their levels.”

Vitamin D and aging: How much you need and how your needs change

Every person’s body and nutritional requirements are different, which is why your vitamin D needs change based on your age and body size. The daily amount of vitamin D, according to the National Institute of Health’s Office of Dietary Supplements (ODS) is 400 international units (IU) for children up to age 12 months, 600 IU for people ages 1 to 70 years, and 800 IU for people over 70 years.

In short, nutrition professionals recommend upping your intake of vitamin D-rich foods (and getting up to 30 minutes of sun exposure daily to help your body synthesize vitamin D) as you get older, particularly for those aged 70 years or older.

If you’re concerned you may be deficient in vitamin D no matter your age, you can get your levels checked by a physician. According to the ODS, levels of 50 nmol/L (20 ng/mL) or more are sufficient for most people, however, the Endocrine Society has stated that a serum concentration of more than 75 nmol/L (30 ng/mL) is necessary to maximize the effect of vitamin D on calcium, bone, and muscle metabolism. The Food and Nutrition Board (FNB) committee also noted that serum concentrations greater than 125 nmol/L (50 ng/mL) can be associated with adverse effects.

Clearly, the only way to truly know if you’re deficient is to get your vitamin D levels checked, and it’s important to do so—as well as consult with a medical professional or dietitian—before starting on any supplements. “If you supplement too much you can get vitamin D toxicity, though this is very rare and usually develops over time,” says Dr. Lana. “Symptoms include high blood pressure, dehydration, frequent urination, increased thirst, irritability, disorientation, nausea and vomiting.” Daily supplementation levels can range from 1,000 IU to 10,000 IU.

According to Dr. Lana, older populations are at greater risk of vitamin D deficiency, particularly if you fit into one of the populations below:

• Those who don’t do weight bearing exercises: “Weight bearing exercises are one of the best ways to improve bone density,” says. Dr. Lana. “Not using muscles can put you at a higher risk for osteoporosis.”
• You have limited sunlight exposure: “The further you are from the equator, the less direct sunlight you receive on an annual basis. Also, the more time you spend indoors, the more you are likely to benefit from extra vitamin D in your diet,” says Dr. Lana.
• You’re pregnant: “Vitamin D is critical for ensuring sufficient embryonic bone and teeth development and for keeping pregnant women’s immune system going strong during such a time of tremendous change”

Vitamin D-rich foods to eat more of at any age

Remember: Though foods sources of vitamin D are relatively limited, you can still up your intake hugely by eating more of a few of these key ingredients:

1. Eggs

One large egg yolks contains about 10 percent of your daily value of vitamin D, says Lockwood-Beckerman. That means a three-egg omelet hits 30 percent of your daily intake—sold.

2. Salmon

Lockwood-Beckerman says that three ounces of salmon provides 78 or more percent of your daily intake, which means anywhere from 550 to 900 IU.

3. Tuna

Tuna is another delicious type of fish with plenty of vitamin D. One 3.5 ounce serving of the fish provides roughly 269 IU, or 38 percent of your daily requirement. Whether you reach for a tuna salad sandwich or just top of your lunch salad with a spoonful of the canned stuff, commend yourself for doing your vitamin D stores a solid.

4. Mushrooms

One of the richest plant-based sources of vitamin D, a cup of white mushrooms brings 46 percent of your daily value to the table. Mushrooms fit effortlessly into all manner of dishes from pizza to stir-fry to soups. Sick of white buttons? Consider this your invitation to mix it up with your go-to mushroom dish—a single cup of morel mushrooms has about 136 IU of vitamin D, which also ain’t bad.

Bottom line? No matter your age, it’s important to get vitamin D levels checked. That being said, it becomes increasingly critical as you age, especially in the cold winter months.

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