As the winter season settles in, so do challenges like shorter days, less sunlight, and an uptick in colds and flu. Vitamins, especially D and C, can play a crucial role in keeping your body healthy during this time.

Dr. Adam Jonas, an internal medicine physician at Kaiser Permanente Everett Medical Center, emphasizes that vitamins are “vital for most physiological functions,” including immune support and bone health. Just remember to consult your clinician before adding supplements to your routine.

Vitamin D: The sunshine vitamin

Vitamin D is essential during winter when natural sunlight is limited. “Vitamin D is critical for overall bone health and immune function,” explains Dr. Jonas. Though our bodies can synthesize it from sun exposure, northern latitudes and shorter days mean supplementation might be necessary. Fatty fish, such as salmon and mackerel, and fortified foods are good dietary sources. However, Dr. Jonas notes, “It’s challenging to meet your daily needs through diet alone in winter.”

Experts recommend vitamin D supplements for certain groups, as deficiency is common. Recommended amounts vary by age. Speak to your clinician about dose if you have never before taken Vitamin D. It is important not to consume too much, as Vitamin D is a supplement that can lead to toxicity and cause negative symptoms if over consumed.

Vitamin C and immune support

Vitamin C is often associated with preventing colds and supports the immune system by promoting white blood cell function. While it won’t necessarily stop a cold, Dr. Jonas reassures that it “can reduce the duration and severity of symptoms.” Citrus fruits, bell peppers, and strawberries are excellent sources and are easy to add to your diet.

Balanced diet first, supplements second

For most adults, a balanced diet provides sufficient vitamins. “We encourage people to think about their diet first,” says Dr. Jonas. He adds that food-based nutrients are more easily absorbed than those from supplements. However, for individuals with specific deficiencies or dietary restrictions, targeted supplements may be beneficial.

Avoid over-supplementation

While vitamins are essential, over-supplementation can cause harm. Fat-soluble vitamins like A, D, and K can accumulate in the body and reach toxic levels if taken excessively. For instance, high doses of cod liver oil, which contains vitamins A and D, could lead to adverse effects. Dr. Jonas advises, “Always discuss your supplement regimen with a health care provider to ensure safety and compatibility with medications.”

Practical tips for winter health

In addition to taking supplements responsibly, Dr. Jonas recommends staying active and getting outdoors when possible. Regular exercise improves circulation, helping deliver nutrients throughout the body. A diet rich in fruits, vegetables, and healthy fats will further support your immune system and overall well-being.

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