advertisement



Q & A Library


Print this page | Sign up for free e-bulletins
 | Bookmark This Page

Q
How Much Vitamin K for Strong Bones?

What do you think of taking 45 mg of vitamin K2 daily to keep bones strong?

A
Answer (Published 7/22/2011)

Vitamin K is necessary for normal blood clotting, and it regulates calcium in the body, keeping it in the bones and out of the arteries. Adequate vitamin K intake also appears to reduce the risks of both heart disease and cancer.

Related Weil Products
Dr. Weil's Vitamin Advisor for Supplements & Herbs - If you are interested in supplementing your diet, and want to take the mystery out of choosing vitamins, try Dr. Weil's Vitamin Advisor. Visit today for your free, personalized Dr. Weil's Vitamin Advisor Recommendation.

There are two main forms of vitamin K. Phylloquinone or vitamin K1 comprises about 90 percent of the K we get from fruits and vegetables. (Good sources include cauliflower, parsley, kiwifruit, avocadoes, olives, Brussels sprouts, broccoli, and dark leafy greens). Vitamin K2 comes in part from the conversion of K1 in the gastrointestinal tract by gut flora as well as from dietary sources, including some types of meat, egg yolks, fermented dairy products (yogurt and some natural, ripened cheeses) and fermented soy foods, like miso and natto.

You ask about taking 45 mg of vitamin K2 daily to keep bones strong. That's way too much - intake of vitamin K1 and K2 should be in micrograms (mcg), not milligrams (mg).

The Adequate Intake (AI) for vitamin K1 established by the Food and Nutrition Board of the U.S. Institute of Medicine is 120 mcg for men age 19 and older and 90 mcg for women age 19 and older. Regarding bone health: the Nurses' Health Study that followed more than 72,000 women for 10 years found that those whose vitamin K intakes were lowest had a 30 percent higher risk of hip fracture than those with the highest vitamin K intakes (at least 110 mcg). Another study involving more than 800 elderly men and women participating in the Framingham Heart Study found that those with the highest dietary vitamin K intakes had a 65 percent lower risk of hip fracture than those with the lowest intakes. Even though there were fewer broken bones, the investigators found no association between dietary vitamin K intake and bone mineral density.

If you're taking a daily multivitamin, it should contain some vitamin K2, typically 10 to 25 mcg, which should be adequate in combination with dietary sources if your bone density is normal. If you have osteoporosis or osteopenia, you should take a daily supplement providing 50 to 100 mcg of this vitamin. The Nurses Study found that eating a serving of lettuce or other green, leafy vegetable daily cut the risk of hip fracture in half when compared with eating one serving a week.

If you're taking anticoagulant drugs, don't take vitamin K supplements or increase your dietary intake without consulting your doctor.

Andrew Weil, M.D.

Creative Commons License Some Rights Reserved Creative Commons Copyright Notice
A portion of the original material created by Weil Lifestyle, LLC on DrWeil.com (specifically, all question and answer-type articles in the Dr. Weil Q&A Library) is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.

The Weil Vitamin Advisor
Get your FREE personalized vitamin recommendation & supplement plan today!

Dr. Weil on Healthy Aging
Your Online Guide to the Anti-Inflammatory Diet. Start eating for your health - begin your free trial now.

Dr. Weil's Spontaneous Happiness
Achieve emotional well-being
in just eight weeks!
Start your 10-day free trial now!

Vitamin Library
Supplement your knowledge with Dr. Weil's essential vitamin facts. Learn why they are necessary and more.

Dr. Weil's Optimum Health Plan
Your 8-week plan to wellness.
Begin your journey today!
 

Dr. Weil's Head-to-Toe
Wellness Guide

Your guide to natural health.
Use the Wellness Guide today!

Dr. Weil's Anti-Inflammatory Diet Food Pyramid
Our interactive tool can help improve overall health through diet.

Condition Care Guide
Learn about health conditions from acne to vertigo, and Dr. Weil's view of the best treatment options for each.

Healthy Recipes
Discover a treasure trove of healthy, healing foods and creative, delicious ways to prepare them.

Q&A Library
Over 2,000 questions from you
and their corresponding answers
from Dr. Weil.

 
Copyright © 2014 Weil Lifestyle, LLC
Information on this web site is provided for informational purposes only and is not intended as a substitute for the advice provided by your physician or other healthcare professional. You should not use the information on this web site for diagnosing or treating a health problem or disease, or prescribing any medication or other treatment.

Ad Choice
Advertising Notice

This Site and third parties who place advertisements on this Site may collect and use information about your visits to this Site and other websites in order to provide advertisements about goods and services of interest to you. If you would like to obtain more information about these advertising practices and to make choices about online behavioral advertising, please click here