Befitting for your bone health
Nutrition and bone health are closely associated. Poor nutrition leads to suboptimal bone health. Although osteoporosis (weak and brittle bones) and osteomalacia (softening of bones) have complex etiologies, the development of these diseases can be minimised by providing adequate amounts of nutrients throughout the lifecycle.
With the right kind of dietary intake and exercise, the reduction in bone density and, in turn, development of osteoporosis can be prevented. Calcium, vitamin D, protein, and vitamin K are nutrients for optimal bone health and present a preventive role against bone diseases.
Calcium: This is the major building block of the bone. It is a myth that calcium supplements are better than the calcium absorbed from food (dietary calcium). The bioavailability of calcium from milk is highest and greater than from supplements. Milk and dietary calcium work better for balancing calcium needs. In the case of lactose intolerance, the degree of lactose intolerance varies in individuals.
Enzymes such as lactaid and maxilact are available, which digest 90% lactose in milk. Some tolerate fermented and cooked milk products such as buttermilk, curds, custards, and cottage cheese, or when mixed with cereals or cocoa for better tolerance. Some tolerate up to 200ml of milk a day.
Food sources: Milk, paneer, ragi, agathi leaves, drumstick leaves, and soya.
Vitamin D: One requires vitamin D for optimal calcium absorption. Calcium and vitamin D go hand in hand. Vitamin D synthesis takes place in the skin when it is exposed to sunlight, especially ultraviolet B rays. In children and adults, sunlight exposure to the skin of hands, forearms, and face for 10 to 15 minutes is sufficient to produce vitamin D depending on the time of the day of exposure. For the elderly, however—given that they may spend more time indoors—vitamin D supplements may be necessary.
Food sources: Oily fish such as salmon and sardines, mushrooms, eggs, liver, and, in some countries, fortified foods.
Vitamin K: In addition to its role in blood clotting, it plays a role in bone health as well. Vitamin K activates proteins involved in bone formation and the mineralisation process that makes bones strong. Osteocalcin, a bone-specific protein made by osteoblasts, requires vitamin K for maturation. Vitamin K comes in two forms. Vitamin K2 has a more protective effect on bone than vitamin K1. However, deficiencies of both K1 and K2 appear to have a negative effect.
Food sources: Green leafy vegetables, cabbage, lettuce, cauliflower, eggs, and chicken breast.
Protein: Adequate protein intake during growth is important for optimal development. During adulthood, it is important to maintain and later avoid decline in bone density. Lack of protein affects muscle strength and increases risk of falls.
Food sources: Pulses, whole grams, soya, eggs, milk and milk products, chicken, fish.
Other nutrients: Adequate intake of fruits and vegetables has been shown to reduce risk of loss of bone density due to multiple vitamins and minerals present in fruits and vegetables. Other nutrients that have protective effects on bone density are vitamin B6, vitamin B12, vitamin A, magnesium, phosphorous, manganese, boron, copper, and zinc. Isoflavones in soy are estrogen agonists and antioxidants in bone cells. Isoflavones stimulate osteoblastic bone formation and inhibit osteoclast bone resorption.
Exercise: Exercise regularly especially weight-bearing activity and muscle-strengthening exercise promises to be protective against muscle and bone loss. Exercise helps in bone-building during childhood and maintains bone during adulthood and beyond.
What to avoid
- Avoid smoking and second-hand smoking.
- Avoid heavy drinking (allowance 1-2 serves, 2-3 times per week).
- Tea/coffee of more than three cups decreases the absorption of calcium and causes a lower bone mineral density (BMD).
- Soft drinks and aerated drinks containing caffeine are to be avoided leading to lower BMD.
- Sodium if high with low calcium intake leads to osteoporosis because it results in increased calcium excretion.
A healthy diet that includes adequate consumption of calcium, vitamin D, and protein is more effective for bone health maintenance than vitamins and other supplements.