Your mother told you, your grandmother told you. Television tells you, “Milk, it does a body good.” For sure, yet we do not realize the true nutrient benefit until you examine the major mineral ingredient in milk – calcium. Look around you, calcium is everywhere: The limestone in your driveway, the coral rock in the Florida Keys, the stalagmites in the Florida Caverns, the pearls you wish you had around your neck, the marble in your head (oops, wrong marbles), your teeth (hopefully you still have them) and in your bones.
Calcium is the fifth most abundant element in the earth. It does a body good because you need it for blood coagulation, muscle contraction, glandular secretion and mutons (cell division). Every plant and animal tissue contains calcium as does the food intake of all animals is rich in calcium except for humans. Oh, yes, our food used to be right in calcium density in food. Chimpanzees in the wild and our hunter-gatherer relatives had high calcium nutrient densities in their diets because they consumed far more greens and leafy vegetables per calorie that we do today. As we have learned to grow cereal grains (rice, corn, wheat) we have increased their energy or starch content while decreasing their calcium and other mineral content. Grains naturally occurring in the wild had a greater mineral content, i.e., more calcium.
During these past 10,000 years of our agricultural revolution our bodies have not evolved to equalize the decrease intake in calcium, so our needs are there but not the sufficient amounts. We do not absorb calcium as efficiently as our ancestors did. Would you believe our ancestors 10,000 years ago actually had larger bones and were structurally larger people.
Growth and Density of Bone Mass
Most of us have observed that infants triple their weight in the first year which is primarily due to the bone mass increase. Unless, of course, your child is overfed, then some of that weight becomes fat, not just bone mass. Most of the bone mass will be created by 18 years of age, while after age 18 we begin to lose some density in the femur (thigh) and upper vertebrae. Scary, huh!? What is even scarier is our decrease in calcium intake during the greatest bone density years.
You know what I mean. Your kids usually will consume milk fairly voluntarily until age 10. Some children need to be coaxed or bribed or “Hello, chocolate milk.” Certainly few kids are willing to eat green veggies unless you are luck enough to have a weird kid who likes veggies, then you may have a mutant on your hands.
In early adolescence it just doesn’t seem cool to drink milk. The child becomes more independent, peers take over, colas enter the scene, and here in lies a major problem. Parents (attention), please read this to your children, particularly between ages 9 to 17. Calcium needs are greater during adolescence than in either childhood or adulthood, states Clinics in Applied Nutrition, Vol. 2, Fall, 1992. During this growth period, the child experiences the greatest muscular, skeletal and sexual development. By age 10, the height increases two inches per year in girls and peaks at 2 ½-2 ¾ inches per year by age 12. Peak height for boys starts at age 12 (2 inches per year and reaches maximum (3 inches per year) by age 14. Growth usually stops at age 15 for girls and 17 years for boys. For both sexes, between ages 11 and 14 years, 37% of the adult skeletal mass is accumulated. So your calcium metabolism is greatest during infancy and adolescence.
Amounts of Calcium Needed
Children from early childhood, age 2, throughout adolescence need 800 mg. of calcium daily. Female adults need 1,000 mg. of calcium daily. After menopause up to 1,500 mg. daily is recommended. Men need 1,000 mg. of calcium daily. These recommended amounts may change in the next few years as more is learned about the role of calcium in our bodies. For example, calcium helps maintain our heartbeat. It must b present for the reception and interpretation of nerve impulses. Calcium helps regulate blood pressure. It also helps to regulate muscle tone in blood vessel walls.
OK, so now I know I need it, where do I get it? (Glad you asked!)
Obviously, dairy products are a good source of calcium, particularly the low fat variety. For example
1 cup milk (skim 1%) = 300 mg. calcium
1 cup yogurt = 300 mg. calcium
1 oz. cheese = 280 mg. calcium
Yet, calorie-wise, greens have more calcium per 100 calories. Spinach, collards and other greens contain 450 to 700 mg. of calcium per 100 calories.
The dilemma is absorption. Dairy products are the most absorbable form of calcium. Greens contain oxalic acid which hinders calcium absorption. Vitamin D, magnesium and phosphorus also help absorb calcium. For older women (Jack Benney’s age of 39 which translates to 65 or greater), Vitamin D3 is recommended but is usually by prescription only as Rocaltrol (by Ross Labs).
Calcium supplements are the last alternative if you cannot consume dairy products (lactose intolerance or milk allergies or just plain stubborn). Today’s recommendation is to take a calcium supplement with a meal.
In the beginning we want to grow, so we need our calcium. In later years we don’t want to shrink, so we need our calcium. It’s a habit/. Consume it and you’ll be better off just like your mother told you. Do you remember the story of the little old lady who fell walking across the street and broke
her hip. That is not what happened. She was walking across the street alright, but her hip crumbled and the fall was after the fact. She had developed osteoporosis, brittle bones. Drink your milk, eat your veggies, listen, dahling!
– Freddy Kaye, Ph. D. is a clinical nutritionist in private practice and the faculty nutritionist at Tallahassee Memorial Regional Medical Center teaching resident physicians diet therapy.