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The Athlete’s Kitchen
Copyright: Nancy Clark MS RD CSSD, August 2009
“I’m 44. Should I start taking calcium pills?”
“A bone density test indicated I have the bones of a 70 year old—and I’m only 34. I guess I should have had more milk and less soda as a kid…?”
“Will drinking more milk help my stress fracture heal faster?”
Questions and confusion abound about the role of calcium in athletes’ diets. If you are like most active people, you may think, “Milk is for kids” and quench your thirst at lunch and dinner with (diet) soda or water. As a result, you can easily end up consuming a calcium-deficient diet (that is, unless you consume yogurt and cheese instead of milk).
Weight-conscious women, in particular, are known to have calcium-deficient diets out of (the unjustified) fear that milk’s calories will add to undesired weight gain (1). Many men also have calcium-poor diets. If they are not milk drinkers, means’ main sources of calcium are from the cheese on cheeseburgers and pizza. Not very health enhancing…
Given the average American lives for 77.7 years, maintaining bone health throughout the lifespan should be a priority for all athletes, starting as youngsters and continuing as master’s athletes. A calcium-rich diet, weight-bearing exercise (such as running, as opposed to biking and swimming) and strength-training to have strong muscles tugging on bones are all important factors for optimizing the bone density of both growing children and active adults.
Bones are alive and require a life-long calcium intake. If your family has a history of osteoporosis, your risk for “shrinking” (losing height) as you get older is high and you should pay special attention to maintaining your bone density. Female athletes with a history of amenorrhea also have a high risk for weak bones and should get their bone density tested so they know where they stand and if they need to take extra steps to try to enhance bone density. Here’s some information about calcium and bone health to help you enjoy lifelong health, no bones about it.
Q. Can I take a calcium supplement instead of drink milk?
A. While any calcium is better than none, taking a calcium pill does not compensate for a calcium-poor diet. A supplement offers calcium, but it does not offer the high-quality protein found in milk or soymilk, nor the myriad of other health-enhancing nutrients. Little babies thrive on milk, not calcium pills. Do you really think a pill can replace a whole food?
Q. I like to save calories by taking a calcium pill instead of drinking milk. Is that OK?
A. Not really. Although a calcium pill offers a low calorie alternative to consuming the recommended three (8-ounce) glasses of milk or yogurt each day, research indicates milk drinkers tend to be leaner than milk avoiders (1). I encourage my clients to embrace milk as a “liquid food” that is satiating and curbs one appetite. That is, milk can be more filling than the same number of calories from soda or juice.
Most of my active female clients reduce weight on 1,800 calories; men on 2,100+ calories. That breaks down to 500 to 600 calories per meal (breakfast, lunch, dinner) and 300 calories for a snack. Enjoying low-fat (soy) milk on cereal, a mid-morning latte and a yogurt for a snack seems a powerful way to spend 300 of those calories and approach the recommended intake of 1,000 milligrams of calcium per for adults 19-50 years; 1,200 mg for adults older than 50 years, and 1,300 mg for kids 9-18 years. If you are a parent, be a role model and drink milk at dinner to encourage a calcium-rich intake for your kids. Building strong bones during the ages of 10 to 18 is a wise investment for the future.
Q. I’m lactose intolerant. Can I get enough calcium from non-dairy foods like soymilk, spinach, broccoli and almonds?
A. For certain, you can get calcium from non-dairy sources. Soy milk is calcium-fortified and offers ~300 mg calcium in 8 ounces—similar to cows’ milk. Other convenient non-dairy calcium sources include fortified orange juice (350 mg/8 oz.) and fortified breakfast cereal, such as Total Cereal (1,000 mg/3/4 cup).
If you are do not consume dairy products or fortified soy products, you will have to work hard to consume adequate calcium. For example, to get the recommended intake from plant sources, you’d need to eat 10 cups of spinach salad, 3.5 cups of broccoli, and 4 ounces almonds (about 88 almonds @ 675 calories). That’s a lot of eating…
What you do NOT get from those plant sources of calcium is Vitamin D. Vitamin D enhances the absorption of calcium and is needed to not only protect bone health but also to reduce the risk of high blood pressure, diabetes, and heart disease; enhance immune function and reduce inflammation. Vitamin D is added to milk and some brands of yogurt, but is hard to find naturally in foods other than oily fish. Hence, non-milk drinkers have a high risk for not only calcium but also vitamin D deficiency.
Q. I live in Boston and spend lots of time outdoors in the sun. Should I take additional D even though I drink milk?
A. Yes, especially between Thanksgiving and Easter. Vitamin D deficiency is surprisingly common in people who live in northern latitudes (north of Atlanta GA), where the sun’s ultraviolet rays do not effectively convert the body’s inactive form of D (just under the skin) into an active form. And even Southerners need to be mindful. A study of southern distance runners indicates 40% of them were D-deficient (2). Indoor athletes (dancers, swimmers, hockey players, figure skaters, basketball players, gym rats, etc.) should ask their doctors about getting their blood tested to determine their level of vitamin D, and if it is low, take steps to correct the problem.
Q. Does the fat in milk contribute to heart disease?
A. Controversial. A study that tracked the health and dairy intake of 4,374 children for 56 years (between 1948 and 2006) reports there was no increased risk of heart disease or stroke among the 34% who died during that time—even though, as kids, the subjects in the study drank whole milk. In fact, the children who consumed the most milk and cheese lived longer. (3)
This study conflicts with the prevalent message to reduce the risk of heart disease by limiting the intake of milk’s saturated fat. Until more research clarifies this confusion, I recommend you enjoy low fat dairy/calcium-rich foods to help reduce excessive fat and calorie intake while maintaining a strong calcium intake.
Q. Will drinking extra milk help a broken bone heal faster?
A. Doubtful. Bones need time to heal … about 6 to 8 weeks. But perhaps you can reduce the risk of breaking a bone by building it stronger in the first place?
Do you get enough Calcium? What are some of your favorite Calcium Rich Foods?
Nancy Clark, MS, RD, CSSD (Board Certified Specialist in Sports Dietetics) counsels both casual and competitive athletes in her private practice at Healthworks, the premier fitness center in Chestnut Hill MA (617-383-6100). Her Sports Nutrition Guidebook, and food guides for new runners, marathoners, or cyclists are available via www.nancyclarkrd.com. See also sportsnutritionworkshop.com for information about upcoming workshops in Providence, Boston and Toronto.
1. Heaney R, Davies K, Barger-Lux M. Calcium and weight: clinical studies. J Amer College Nutrition 2002. 21(2):152S-155S.
2. Willis KS, Peterson NJ, Larson-Meyer DE. Should we be concerned about the vitamin D status of athletes? Int’l J Sports Nutr & Exerc Metab 2008 18:204-235.
3. van der Pols JC, Gunnell D, Williams G, Holly J, Bain C, Martin R. Childhood dairy and calcium intake and cardiovascular mortality in adulthood: 65-year follow-up of the Boyd Orr cohort. Heart. 2009; July 29. (Epub ahead of print)
Copyright: Nancy Clark MS RD CSSD July 2009
Sports Nutrtion News from the American College of Sports Medicine
The American College of Sports Medicine (ACSM) is the world’s largest sports medicine and exercise science organization. At ACSM’s annual meeting in Seattle, May 27-30, 2009, over 5,000 exercise scientists, sports dietitians, physicians and health professionals gathered to share their research. Here are a few of the nutrition highlights. More highlights are available at www.acsm.org (click on “news releases”).
• Many athletes believe protein supplements are needed for building muscle. Yet, a study with college football players indicated no performance or muscle-building advantages from taking recovery protein in the form of a commercial supplement instead of standard food.
• Fruits and berries, including tart cherries, have anti-oxidant and anti-inflammatory properties. Runners who drank two 10.5 ounce bottles of tart cherry juice for one week before the 192 mile Mt. Hood to Oregon Coast relay race reported less post-race muscle pain than the placebo group.
• Black currants may also help reduce oxidative stress. Cyclists who consumed a pre-hard ride dose of black currant extract (the equivalent of about 1.2 cups of currants), experienced less oxidative stress.
• Research suggests food tends to be more health-protective than supplements. Taking high doses of C (2000 mg), E (800 IU), A (3000 IU), and selenium (200 micro-g) for six weeks offered no benefits to trained cyclists in terms of antioxidant effects and suppressing oxidative damage.
• Almonds (and all nuts, for that matter) are a positive addition to a sports diet. For four weeks, elite cyclists enjoyed about 60 almonds a day (~450 calories) prior to meals. They increased their anti-oxidant capacity 43% after a time trial as compared to the group who ate an equal number of calories from cookies. They also improved their time trial distance by 5% compared to the cookie group.
• Just rinsing your mouth with a sports drink may help you run faster! After an overnight fast (13-15 hours without food) and before and during a one hour time trial, 10 trained runners rinsed their mouth for five seconds with a sports drink or a placebo, and then spit it out. With the sports drink mouth rinse, they were able to run 365 meters longer in the time trial.
• An effective sports drink needs to be rapidly absorbed. Adding sodium (40-165 mg) to the beverage does not significantly slow absorption. (1973)
• Athletes who exercise in the heat might wonder if they can “hyper-hydrate.” Yes; more fluid is retained when a sports drink has a higher sodium content. Drinking a sports drink with double and triple the standard amount of sodium contributed to retaining 25% and 35% more water (12 and 17 ounces; 340 and 480 ml) than the standard sports drink.
• About 25% of athletic trainers use pickle juice to treat muscle cramps. Some report 1 to 2 ounces of pickle juice relieves cramps within 35 seconds. The mechanism is illusive because rapid relief must mean that pickle juice empties from the stomach very quickly. Yet, research indicates pickle juice empties very slowly from the stomach.
• “LactAway” is a sports supplement that claims to reduce blood lactate. A study with highly trained kayakers does not support that manufacture’s claim.
• Chocolate milk is a good recovery choice. Cyclists did an exhaustive bike ride, recovered with equal amounts of carbs in chocolate milk or a commercial recovery drink, and then the next day did a time trial. The commercial drink offered no additional benefits. Save your money!
• Glutamine is reported to enhance recovery by reducing post-exercise inflammatory responses. A study that compared a carbohydrate+essential amino acids beverage with or without glutamine taken during and after exercise offered no additional recovery benefits.
• Of 153 female soldiers starting basic training, 37% were iron deficient (serum ferritin <12 ng/mL). The women who took an iron supplement (100 mg ferrous sulfate) improved their two-mile run-times by 86 seconds as compared to the iron deficient women who were given no iron pills. Low ferritin is associated with feelings of depression and fatigue.
• During endurance exercise, consuming carbs in the form of an energy bar, a gel or a sports drink are all equally effective. That is, they all get used for energy at a similar rate.
• Many youth swimmers spend hours training for relatively short competitive events. A six-week study with 9 to 12 year olds suggests high intensity/low volume training offers the same benefits as lower intensity/high volume training (27 vs. 57 km/six weeks)—but in far less training time.
• How may calories are burned when lifting weights? Female subjects burned ~100 calories and the males ~ 210 in the half-hour session with two sets of 10 reps and 8 different exercises. But, if you subtract the calories for the resting metabolic rate that they would have burned just sitting quietly, they burned only ~70 (females) and ~160 (males) additional calories.
• Participants in the Western States 100 Mile Run burned about 15,850 calories in about 27 hours. This averaged about 600 calories/hour. That’s a lot of food!
• Severely obese people may need about 1800 calories just to be alive, and about 3,200 total calories a day. They don’t gain weight just smelling cookies…
• Exercise improves learning. Movement and physical activity in third graders has been linked with higher scores on tests involving problem solving. Among college students, those who spend more than three hours/day studying or have a grade point average of at last 3.5 are more likely to be physically active than students who study less and get lower grades.
• While American college students tend to exercise for weight control, fitness and physical attractiveness, Chinese college students tend to exercise for health and enjoyment—sustainable reasons to exercise!
• The Female Athlete Triad refers to the common problem of inadequate calorie intake, loss of menses, and stress fractures. The first line of treatment is to increase calorie intake or reduce expenditure by exercising a little less.
Strength training can help reduce the risk of stress fractures. Athletes with more muscle mass tend to have higher bone density. Dense bones are healthy bones!
• Fitness is more important than fatness. Unfortunately, only about 9% of Americans are “fit but fat” as compared to 30% who are “fit and not fat”.
What is your favorite work out food? Comment Below!
Nancy Clark, MS, RD, CSSD (Board Certified Specialist in Sports Dietetics) counsels both casual and competitive athletes in her private practice at Healthworks, the premier fitness center in Chestnut Hill MA (617-383-6100). Her Sports Nutrition Guidebook, and food guides for new runners, marathoners, or cyclists are available via www.nancyclarkrd.com. See also sportsnutritionworkshop.com.
(image: flikr, fotonics)