All humans need different amounts of 14 key vitamins and 15 key minerals to survive. Because the average man weighs more than the average woman -- and because men have a higher percentage of muscle compared to women -- men need a higher intake of these nutrients. As men age, they require a higher daily intake of certain vitamins and minerals, so the dietary needs of a 65-year-old man differ from those of an older or younger man.
Regarding daily guidelines for vitamin and mineral intakes, the Food and Nutrition Board -- a branch of the Institute of Medicine within the National Academies -- groups 65-year-old men with all men between ages 51 and 70. Vitamins fit in one of two categories: fat-soluble and water-soluble. Fat-soluble vitamins -- which dissolve in fat -- include A, D, E and K and are more easily stored in the body than water-soluble vitamins; the body needs them in smaller daily amounts. A 65-year-old man daily needs 900 micrograms of vitamin A, 15 micrograms of vitamin D, 15 milligrams of vitamin E and 120 micrograms of vitamin K.
Water-soluble vitamins comprise the remaining 14 vitamins the human body needs to function. These vitamins are dissolved in water, and are easily flushed out of the system through basic body functions like sweating or urinating. For this reason, these vitamins -- C and all B-group vitamins -- must be obtained in larger daily doses. If you are a 65-year-old man, you daily need 90 milligrams per day of vitamin C, 1.2 milligrams of thiamin, 1.3 milligrams of riboflavin, 16 milligrams of niacin, 1.7 milligrams of B6, 400 micrograms of folate, 2.4 micrograms of B12, 5 milligrams of pantothenic acid, 30 micrograms of biotin and 550 milligrams of choline for optimal health.
Fifteen minerals the human body needs are divided into two groups: macro minerals and trace minerals. Macro minerals is the term applied to the six minerals -- calcium, magnesium, phosphorus, potassium, sodium and chloride -- the body needs in large quantities. The body needs a minimum of 100 milligrams a day of each of these six macro minerals, although for some of them, the body needs far more than 100 milligrams a day. The daily macro mineral requirements for a 65-year-old man include 1,000 milligrams of calcium, 420 milligrams of magnesium, 700 milligrams of phosphorus, 4.7 grams of potassium, 1.3 grams of sodium and 2 grams of chloride.
In addition to the six macro minerals, the body also needs smaller amounts -- less than 100 milligrams per day -- of nine trace minerals. A 65-year-old man daily needs 30 micrograms of chromium, 400 micrograms of copper, 4 milligrams of fluoride, 150 micrograms of iodine, 8 milligrams of iron, 2.3 milligrams of manganese, 45 micrograms of molybdenum, 55 micrograms of selenium and 11 micrograms of zinc.
Not all health experts follow the Food and Nutrition Board's guidelines. Talk show host Dr. Mehmet Oz suggests that 65-year-old men daily get 4 milligrams of vitamin B6, split between two 2-milligram doses. The Australian Government's Department on Health and Aging suggests taking in less vitamin D daily -- just 10 micrograms -- than the Food and Nutrition Board's recommendation. Exact requirements for vitamins and minerals may vary depending on an individual's health needs, so check with your physician before taking supplements or reducing the amount of certain nutrients in your diet.