Biggest Nutrition and Food Myths Busted
“A raw-food diet provides enzymes that are essential to healthy digestion.”
“Raw foods are unprocessed so nothing’s taken away; you don’t get the nutrient losses that come with cooking,” says Brenda Davis, R.D., co-author of Becoming Raw: The Essential Guide to Raw Vegan Diets (Book Publishing, 2010). But the claim by some raw-food advocates that eating raw boosts digestion by preserving “vital” plant enzymes, Davis explains, just doesn’t hold water. “Those enzymes are made for the survival of plants; for human health, they are not essential.”
It’s true that heating a food above 118°F inactivates plant enzymes, “since enzymes are proteins and proteins denature [break down] with heat,” explains Andrea Giancoli, R.D., a Los Angeles-based spokesperson for the American Dietetic Association. “But those enzymes are denatured—and thus inactivated—when they reach our stomachs. Our stomach acids are designed to break down proteins very efficiently.” If associated with living microorganisms (such as those in fermented foods like sauerkraut), plant enzymes might reach the small intestine intact, adds Davis, “but their overall contribution to human digestion appears minimal.”
What about the claim by some raw-foodistas that our bodies have a limited lifetime supply of enzymes—and that by eating more foods with their enzymes intact, we’ll be able to spare our bodies from using up their supply? “The reality is that you don’t really have a finite number of enzymes; you’ll continue to make enzymes as long as you live,” says Davis. Enzymes are so vital to life, she adds, “the human body is actually quite efficient at producing them.”
