When I ask students what age is “old,” they might say 60 or 65 years, but they are surprised to hear that by 25, most of our body systems begin to age and decline in function. They all want to know what supplement they can take to prevent the decline and my answer is fourfold:

• Despite claims on the Internet, there is no supplement that can stop or reverse the effects of aging;

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Chris Hunt/AJC

Peach Blackberry Smoothie

Have a question of general interest? E-mail Chris Rosenbloom Fit to Eat columns Five fabulous and healthy foods to feature on Thanksgiving  Cancer survivors improve chances with good diet  Let kids enjoy Halloween — without the guilt         More Fit to Eat • Chris Rosenbloom, Ph.D., R.D., is a member of the nutrition faculty in the College of Health and Human Sciences at Georgia State University Related: • Carolyn O'Neil: You can thank these local chefs for these low-cal holiday recipes  Good links: • Evening Edge • AJC Food & Drink • AJC Health Channel • Diet and Nutrition headlines, resources • Atlanta Restaurant reviews and search • Low fat/ heart healthy recipes • Search recipes

• Choose your calories more carefully (we have less room for empty calories like soft drinks, alcohol and high-fat snack foods as we age);

• Eat more fruits and vegetables (and I don’t mean french fries, fruit roll-ups, or fried onion rings);

• Be active every day, including aerobic activities for endurance and weight training for strong muscles and bones.

Five for 50

If you are older than 50, include these top five foods for good health:

• Fish: fatty fish such as salmon and tuna (canned salmon and tuna count, too) contain omega-3 fats to help lower blood pressure and blood fats such as triglycerides and reduce development of blood clots.

• Nuts: Just a handful a day is all you need but they provide fiber, B vitamins, vitamin E, magnesium and protein. What’s a handful? See below for the number of nuts in 1 ounce.

• Yogurt: Dairy foods pack a protein and calcium boost but also contain vitamin D to better absorb calcium and the B vitamin, riboflavin. Look for yogurt with active cultures. These probiotics help your digestive system.

• Whole grains: Look for the word “whole” as the first ingredient on a label. We should get three servings or 48 grams of whole grains a day. One serving of whole grains contains 16 grams. Whole grains contain plant compounds in addition to vitamins and minerals that help reduce the risk of heart disease and some cancers.

• Cruciferous vegetables: Broccoli, cauliflower, kale and cabbage are packed with healthy plant nutrients, as well as vitamins, fiber and water. Frozen or canned can be a good substitute when fresh is not in season or is too costly.

Calcium: A bit at a time

Your bones love calcium, whether from foods or supplements, but foods get the edge because they contain other nutrients needed for strong bones. If you take a calcium supplement follow these rules:

• Calcium is better absorbed in smaller doses throughout the day instead of in one whopping dose.

• Older adults should choose calcium citrate instead of calcium carbonate — the citrate form is better absorbed as stomach acid production declines with aging.

• If you are taking a biphosphonate drug for osteoporosis (Fosamax or Actonel), don’t take calcium in the morning with the drug. Take your calcium later in the day so it doesn’t interfere with the drug’s absorption.

Go nuts

Enjoy a 1-ounce serving of nuts as a snack. Not sure how many nuts are in a serving? Here’s a handy guide:

Almonds: 24 whole (170 calories)

Cashews: 18 whole (160 calories)

Macadamias: 11 whole (200 calories)

Pecans: 20 halves (200 calories)

Peanuts: 30 whole (170 calories)

Pistachios: 47 (160 calories)

Walnuts: 14 halves (190 calories)

Recipe: Peach Blackberry Smoothie 2 servings

Hands on: 5 minutes Total time: 8 minutes

2 cups vanilla soy milk

2 cups frozen peaches

2 cups frozen blackberries

2 tablespoons almond butter

2 tablespoons honey

In a blender, combine soy milk, peaches, blackberries, almond butter and honey and process until smooth and thick.

— Adapted from www.almondsarein.com (click on “almond lovers” for recipes)

Per serving: 210 calories (percent of calories from fat, 30), 7 grams protein, 34 grams carbohydrates, 5 grams fiber, 7 grams fat (less than 1 gram saturated, no cholesterol, 110 milligrams sodium.

Nutritional bonus points: This drink is rich in protein, fiber, calcium (about 20 percent of daily needs), potassium and vitamin E — all nutrients needed by older adults.