As a Singapore personal trainer and fitness boot camp instructor, I am always encouraging my clients to eat more vegetables. For anyone serious about fat loss, muscle gain, weight loss and fitness, eating vegetables forms a crucial part of the right kind of diet and lifestyle.
Remember, vegetables are great for our health! They have vitamins, minerals, fiber, all manner of anti-oxidants and other beneficial phytochemicals. The antioxidants in vegetables can help slow cataracts and macular degeneration, slow development of heart disease, reduce DNA damage, prevent cancer, moderate inflammation in the body, reduce our own production of DNA-damaging chemicals, slow the body’s removal of calcium from bones etc. In fact, in our gym, vegetables are on the “10 commandments” for a healthful lifestyle that all our personal training and fitness boot camp clients get to read.
So how do we make sure that we benefit from the vegetables we eat?
For that, we need to understand the effect of cooking/not cooking on our vegetables. Also, we need to understand how to keep our vegetables in top shape before eating them, and how to keep them safe for consumption!
Cooking:
Cooking causes many nutrients in food to breakdown, yet it can also make many nutrients more easily absorbed by the body. So, the best healthy diet will include both raw and cooked vegetables. Also, always eat your vegetables with some fat (olive oil, butter etc) to aid absorption of the good stuff in them.
How cooking diminishes nutritional value:
Cooking usually causes a drop in the nutritional value of food, since the lovels of most vitamins, antioxidants, and other beneficial substances because of increased, uncontrolled enzyme activity, high temperature and exposure to oxygen and light. Cooking liquid can also draw out nutrients from vegetables and fruits. Brief and rapid cooking in minimal amounts of water helps keep cooked veggies as nutritious as possible.
How cooking enhances nutritional value:
Cooking destroys some harmful germs. It also softens and concentrates food, so it’s easier to eat enough of them and makes certain nutrients more available to the body. For example, without cooking, we would not be able to absorb starch (our digestive enzymes can’t deal with the tough outer layers of raw starch granules) and carotenoid pigments, such as beta-carotene, and lycopene, which is an important antioxidant. These aren’t very soluble in water, so can’t really extract these chemical well by chewing and swallowing. Cooking breaks up the plant tissues better so we can extract more of them (Adding fat helps us to absorb fat-soluble nutrients better too).
Keeping vegetables safe and in good shape:
Vegetable safety
1. Avoid pre-cutting fruits and vegetables. The tissue damage causes the plant cells to increase biochemical defensive activity, which can reduce amount of remaining nutrients and cause changes like browning, toughing and off-flavors. It also exposes the nutrient-rich interiors to disease-causing microbes. You can coat cut fruits and veggies with something acidic, lemon juice to slow down browning etc.
2. Throw away bad – rotten and moldy etc – fruits and vegetables at once, before they have a chance to “infect” other. Mushrooms, berries, figs, avocados and apricots particularly rot fast. Don’t eat potatoes with green bits – poisonous alkaloids have formed. You might not be able to turn up for your personal training or fitness boot camp sessions the next day.
3. Scrub down and disinfect the places where you regularly store vegetables and fruits (the refrigerator drawers etc) frequently to discourage germs.
4. Don’t “stress” fruits and veggies by packing them too tightly and don’t store fruit or veggies that have been dropped – use them immediately.
5. Soil harbours germs so wash tougher fruits and tubers before storing but don’t wash delicate fruits like berries before storage since even a gentle water rinse will cause their protective epidermal layers to be abraded by the dirt particles.
6. Cook your beans well to make sure that protease inhibitors that interfere with digestion and lectins that interfere with nutrient absorption are destroyed.
7. Eat your produce as fresh as possible. Buy small amounts you can consume within a couple of days, if your schedule permits frequent trips to the supermarket/farmer’s market.
8. WASH everything well (the veggies, knives, cutting boards etc) before food preparation.
Enjoy your vegetable. As our personal training and weight loss boot camp clients have all found, vegetables are delicious and make that difference to your day!
Reference: McGee, H. (2004) On Food and Cooking: the science and lore of the kitchen. Scribner: New York