- With Mayo Clinic nutritionist
Katherine Zeratsky, R.D., L.D.read biographyclose window
Katherine Zeratsky, R.D., L.D.Katherine Zeratsky, R.D., L.D.
As a specialty editor for the nutrition and healthy eating guide, Katherine Zeratsky helps you sort through the facts and figures, the fads and the hype to learn more about nutrition and diet.
A Marinette, Wis., native, Katherine is certified in dietetics by the state of Minnesota and the American Dietetic Association. She has been with Mayo Clinic since 1999.
She is active in nutrition-related curriculum and course development in wellness nutrition at Mayo Clinic in Rochester, Minn., and nutrition education related to weight management and practical applications of nutrition-related lifestyle changes.
Other areas of interest include food and nutrition for all life stages, active lifestyles and the culinary arts.
She graduated from the University of Wisconsin-Madison, served a dietetic internship at the University of Iowa Hospitals and Clinics, and worked as a registered dietitian and health risk counselor at ThedaCare of Appleton, Wis., before joining the Mayo Clinic staff.
Nutrition basics (31)
- Phenylalanine in diet soda: Is it harmful?
- Water softeners: How much sodium do they add?
- Diet soda: Is it bad for you?
- see all in Nutrition basics
Healthy diets (11)
- Canola oil: Does it contain toxins?
- Butter vs. margarine: Which is better for my heart?
- Detox diets: Do they work?
- see all in Healthy diets
Healthy cooking (7)
- When the heat is on, which oil should you use?
- Moldy cheese: Is it OK to eat?
- Food poisoning: How long can you safely keep leftovers?
- see all in Healthy cooking
Healthy menus and shopping strategies (8)
- White whole-wheat bread: Is it nutritious?
- Sodium nitrate in meat: Heart disease risk factor?
- Brominated vegetable oil: Why is BVO in my drink?
- see all in Healthy menus and shopping strategies
Nutritional supplements (18)
- What is wheatgrass — And why is it in my drink?
- Prenatal vitamins: OK for women who aren't pregnant?
- Too much vitamin C: Harmful?
- see all in Nutritional supplements
Vitamin D deficiency
What are the risks of vitamin D deficiency?
from Katherine Zeratsky, R.D., L.D.
Vitamin D deficiency — when the level of vitamin D in your body is too low — can cause your bones to become thin, brittle or misshapen. The role of vitamin D and insulin resistance, high blood pressure, and immune function — and how these relate to heart disease and cancer — is under investigation.
Although the amount of vitamin D adults get from their diet is often less than what's recommended, exposure to sunlight can make up for the difference. For most adults, vitamin D deficiency is not a concern. However, some groups — particularly people with dark skin and adults older than age 65 — may not get enough vitamin D in their diet or get enough sunlight for their bodies to produce it.
The recommended dietary allowance (RDA) for adults is 600 IU of vitamin D a day. That goes up to 800 IU a day for those older than age 70. To meet this level, choose foods that are rich in vitamin D. For example, choose fortified foods such as milk and yogurt and fatty fish such as salmon, trout, tuna and halibut.
Don't over do it, though. Very high levels of vitamin D have not been shown to provide greater benefits. In fact, too much vitamin D has been linked to other health problems.
If you're concerned about whether you're getting enough vitamin D, talk to your doctor about your diet and whether a vitamin supplement might benefit you.Next question
Chocolate: Does it impair calcium absorption?
- Vitamin D. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/sec01/ch004/ch004k.html. Accessed May 7, 2012.
- Dietary reference intakes for calcium and vitamin D. Institute of Medicine. http://www.iom.edu/vitamind. Accessed May 7, 2012.
- Dietary Guidelines for Americans, 2010. U.S. Department of Health and Human Services. http://www.cnpp.usda.gov/DGAs2010-PolicyDocument.htm. Accessed May 7, 2012.
- USDA National Nutrient Database for Standard Reference, Release 24. U.S. Department of Agriculture, Agricultural Research Service. http://ndb.nal.usda.gov. Accessed May 7, 2012.
- Hathcock JN, et al. Risk assessment for vitamin D. American Journal of Clinical Nutrition. 2007;85:6.
- Lee JH, et al. Vitamin D deficiency: An important, common, and easily treatable cardiovascular risk factor? Journal of the American College of Cardiology. 2008;52:1949.
- de Boer IH, et al. Serum 25-hydroxyvitamin d concentration and risk for major clinical disease events in a community-based population of older adults: A cohort study. Annals of Internal Medicine. 2012;156:627.