According to a recent study, a single dose of at least 100,000 IU vitamin D3 rapidly attenuates sunburn when given within one hour of sun exposure. Lower doses were far less effective.
As we get older, our skin is less able to synthesize Vitamin D and as we get older we often spend more time indoors. Vitamin D assists in the absorption of calcium and promotes bone mineralization. Low levels of Vitamin D may contribute to the progression of osteoporosis. Vitamin D also reduces the risk of high blood pressure, psoriasis and some autoimmune diseases. More recent studies show that low levels of Vitamin D can increase the risk of getting cancer.
We need stomach acid for optimal absorption of Vitamin B12, but as we age, our bodies often produce less acid. Many people suffer from heartburn or acid reflux and take over-the-counter or prescription drugs called proton-pump inhibitors (PPIs) or histamine-2 receptor antagonists (H2RAs). These work by inhibiting stomach acid production, raising the risk of vitamin B12 deficiency.
Calcium levels fall after menopause. It is recommended that women supplement with 500 to 700 mg of calcium citrate in two divided doses taken with meals for a total of 1,000 to 1,200 mg a day from all sources (including diet). Instead, I suggest that men try to get 500 to 600 mg of calcium daily through their diets and no supplementation is needed.
After Menopause, there is no need for women to take supplemental iron unless instructed to by a health care provider. Too much iron can be harmful and even increase the risk of cancer.