FACING THE HEAT
So, it seems some foods should be eaten raw, but it remains that others ought to be cooked. Not cooking may prevent loss of nutrients such as the B vitamins, including folate, and vitamin C. But there are nutrients that need to be cooked in order to become more bioavailable, which means our bodies can better absorb them.
“For example, lycopene is an example of an antioxidant that actually increases in concentration in tomatoes when they are cooked as opposed to having them raw,” says Vanessa.
“Also, you can prevent unnecessary vitamin loss by blanching or steaming your vegetables for no more than five minutes,” says Jaclyn Reutens, clinical dietitian at Aptima Nutrition & Sports Consultants. Sauteing may not be such a bad idea either. “Fat-soluble vitamins such as A, D, E and K are released in oil and can be better absorbed by our bodies,” adds Jaclyn.
What’s more, cooking helps reduce oxalic acid, a compound in vegetables such as spinach, sweet potato and endive. It can cause irritation to the mouth and intestinal tract as well as block the absorption of iron and calcium by the body.
Experts also dispute the notion that humans need the enzymes found in raw plants for better digestion. “In healthy individuals, the pancreas is more than capable of producing the enzymes needed for digestion,” says Vanessa.
“They include protease to break down proteins, amylase (carbohydrates), and lipase (fats). These help the foods to be efficiently broken down so that they can be used by the small intestines,” she explains. However, this might not be the case for people with conditions like chronic pancreatitis (inflammation of the pancreas).
Raw foodists also run the risk of food poisoning. “Humans started cooking for a reason – and it is to kill bacteria,” says Pooja Vig, nutritional therapist at The Nutrition Clinic. Besides, heating food to 47 deg C is not enough to zap germs. According to the Agri-food & Veterinary Authority of Singapore, bacteria multiply the quickest at temperatures between 5 deg C and 60 deg C.
Plant foods have also been found to be more susceptible to contamination. “Bacteria such as E.coli, salmonella and listeria can contaminate plant foods through soil. They can cause nasty foodborne illnesses,” notes Vanessa. “It pays to rinse fruits and vegetables thoroughly, including pre-packaged, pre-washed salads,” she adds.
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