Ask the Experts

Calcium requirements vary around the world because they are influenced by other components of the diet that vary around the world. For example, dietary fiber can reduce calcium absorption. High sodium (salt) intake increases calcium losses through the urine.

For a corn tortilla to be considered a whole grain product, it must be made with whole grain corn flour, and this will be indicated on the ingredient list with words such as 'whole corn' or 'whole grain corn flour.'

Fortunately for those who avoid meat and meat products, there are numerous other suitable protein sources to choose from. Protein is comprised of building blocks' called amino acids that our bodies need to function. Though meat is a notable protein source because it contains all nine of the essential amino acids (which we must get from food), it is not the only one - eggs, dairy and soy products (like soy milk and tofu) also provide all of the essential amino acids in the desired proportions.

Beetroot juice is currently a 'hot' nutritional supplement for its touted effects both on reducing cardiovascular disease risk and its potential to improve endurance exercise performance. Beetroot is naturally high in nitrate, which is converted to a signaling molecule called nitric oxide in the body. Nitric oxide has beneficial effects on vasodilation (relaxation and widening of blood vessels, increasing blood flow).

Our reward center in the midbrain gets activated for the prospect of food and available food of a kind we like, so until our sensory-specific satiety mechanism tells us the portion size is sufficient, addictive chemicals are released, such as dopamine, to keep us eating.

Based on available research, the usual 'healthy diet' is the best one can do. That includes a high (5 or more servings daily) intake of fruits and vegetables (including dark leafy greens), some dark (fatty) fish and whole-grain products, but lower in refined carbohydrate and sugars." Why the emphasis on carbohydrate quality?

Tea (from the Camellia sinensis plant) is a rich source of flavonoid phytonutrients, which function as antioxidants. The amount and relative proportion of these compounds in tea leaves depends on a variety of factors, including growing conditions, post-harvest processing (including the fermentation that converts green tea to oolong and black teas) and storage time before brewing. The form of tea, whether as loose leaf or the broken leaf (pekoe) and even smaller particles (fannings or dust) in bags, is not a clear determinant of its antioxidant capacity.

For maximal absorption of calcium from supplements, no more than 500 to 600 milligrams (mg) of elemental calcium should be taken as a single dose. For the few people who require more than 500 to 600 mg of calcium in supplement form, the dose should be split. For best absorption, calcium carbonate should be taken with meals. Calcium citrate may be taken anytime.

Nutrient loss with heat is not unique to roasting. Other forms of cooking can also reduce heat-sensitive nutrients, and cooking methods that use water, such as boiling, result in nutrient losses from water-soluble nutrients leaching into the water. "So, consider varying your preparation methods, such as by eating raw vegetables and salads as well as roasted, steamed or sauted vegetables.

While it is true that an enteric coating would protect the probiotic from acid killing in the digestive tract, if the probiotic is part of a food matrix such as yogurt, the buffering capacity of the yogurt or kefir would also act as an effective protector against stomach acid.