Vitamin D is more important for our health than many realize. While it’s commonly associated with bone health, new research highlights its broader impact.

1. Hair thinning and hair loss When your body lacks vitamin D, it can disrupt hair growth. The cells responsible for your hair cycle, called keratinocytes, struggle to function properly. Low vitamin D levels shorten the growth phase of hair and extend the resting phase. Plus, the layer supporting your hair (the dermic layer) weakens, making hair loss more likely. Deficiency in vitamin D is also linked to conditions like alopecia areata, which causes small bald patches on the scalp or beard.

2. Dry, itchy skin Vitamin D is essential for healthy skin. Skin cells called keratinocytes, which make up the outer layer, are unique in that they can convert a precursor into usable vitamin D. This vitamin strengthens your skin’s barrier, promotes skin cell growth, and supports its immune defense. Low vitamin D levels have been linked to skin conditions like eczema and psoriasis, which can cause dry, irritated skin. Supplements can improve these symptoms by making the skin less dry and itchy.

3. Pins-and-needles sensation in hands or feet Low vitamin D can result in decreased calcium levels, which might cause a tingly or “pins-and-needles” feeling in your hands or feet. These sensations are a sign that your body’s mineral balance is off. Getting enough vitamin D not only supports bone health but also keeps calcium levels stable, preventing discomfort.

4. Muscle weakness Vitamin D deficiency increases the risk of losing muscle strength, especially with age. A study involving over 3,200 people aged 50+ found that those with insufficient vitamin D were more likely to develop muscle weakness. Since muscle strength is crucial for preventing falls as we age, maintaining adequate vitamin D levels helps reduce this risk.

5. Pale skin and dark circles A lack of vitamin D can make your complexion appear dull or slightly gray, and you may notice darker circles under your eyes. Vitamin D is vital for the renewal of skin cells. Without it, your skin struggles to rejuvenate, leading to these visible changes. Keeping vitamin D levels up promotes healthy, vibrant-looking skin.

6. Changes in sleep and mood Low vitamin D is linked to mood swings and disrupted sleep. Vitamin D affects brain chemicals like serotonin and melatonin, which are essential for regulating mood and sleep patterns. It even plays a role in how your body produces melatonin, which helps regulate your sleep-wake cycle. Proper vitamin D levels support better sleep and a more balanced mood.

7. Bone and lower back pain Vitamin D helps your body absorb calcium, which is crucial for bone health. If you don’t get enough, you might experience bone pain or lower back pain. Research has found that people with arthritis or chronic pain often have lower levels of vitamin D. Although not all studies agree, ensuring adequate vitamin D through sunlight, diet, or supplements can contribute to stronger bones and reduced pain.