September 28, 2022


For First-Rate Health

Is food enough? | University of Nevada, Reno

This article was originally published in the Healthy Aging Initiative‘s October newsletter. The Initiative, an offering of Extension, provides physical activity and nutrition education and health promotion to elders throughout Nevada.

Getting the necessary vitamins and minerals your body needs from food is preferred over supplements. This is because foods usually give you other nutrients too. However, sometimes it is difficult to get all the vitamins and minerals you need from the foods we eat. Older adults often do not get enough calcium or vitamins D and B12 from their diet.

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Calcium is a major part of bones and plays an essential role in other functions in the body. If dietary intake of calcium is not adequate, the bones are used as a source to keep blood calcium levels normal. Men 70 years and under and women 50 years and under should consume 1,000 milligrams a day. Men 71 years and older and women 51 years and older need 1,200 milligrams a day.

Many foods have calcium; dairy products contain the most, and leafy green vegetables can also be a good source according to Food Sources of Calcium – Dietary Guidelines for Americans.

Common forms of calcium supplements are calcium carbonate (to be taken with food) and calcium citrate (can be taken with or without food). The body best absorbs about 500 milligrams of calcium at a time so you may need to take it more than once a day. The absorption of calcium supplements can be affected by medications so check with your pharmacist.

Vitamin D

There has been a lot of information about vitamin D in the news the last few years; some scientifically proven, some not. What we do know is the body needs vitamin D for calcium absorption and low levels are a risk factor for falling. The recommendations for how much vitamin D you should take is 20 to 25 micrograms a day (800 to 1,000 international unit) for men and women over 50 years old.

Some foods have vitamin D added to them, but very few contain it naturally. Freshwater trout, salmon and tuna are among the highest sources, according to Food Sources of Vitamin D – Dietary Guidelines for Americans.

Vitamin D is available as an individual supplement or in combination with other vitamins/minerals. Do not take more than 100 micrograms (4,000 international unit) daily unless told to do so by your health care provider.

Vitamin B12

The body uses vitamin B12 to maintain healthy nerve cells and make red blood cells. The Recommended Dietary Allowance of vitamin B12 for adults 50 and older is 100 to 400 micrograms/day.

Low levels of vitamin B12 occur because it is not absorbed well in the body or the diet does not contain enough. Medications, like metformin (to treat diabetes) can decrease vitamin B12 absorption.

Beef liver is an excellent source of vitamin B12 according to Vitamin B12 – Fact Sheet for Health Professionals, and multiple vitamins and other supplements contain vitamin B12.

Leslie Baker is a board certified geriatric pharmacist and director of geriatric pharmacy services at the Sanford Center for Aging, a unit of the University’s School of Medicine.

For more information about healthy aging, visit the Healthy Aging Initiative website, an offering of ExtensionAn EEO/AA Institution.

Extension is a unit of the University’s College of Agriculture, Biotechnology & Natural Resources engaged in Nevada communities, presenting research-based knowledge to address critical community needs. It is a county-state-federal partnership providing practical education to people, businesses and communities.