Want to get the optimum nutritional
value from your food? It's all in the preparation
You can boost the nutrients in some basic
foods by preparing or eating them in a certain way. Here we look at what the
research says about how to get the most from some of those foods.
Cook tomatoes
Whether fresh or tinned, cooking tomatoes
improves how our body uses the chemical lycopene - a natural antioxidant that
helps prevent disease. You absorb more lycopene from cooked tomatoes.
Whether
fresh or tinned, cooking tomatoes improves how our body uses the chemical
lycopene
"Tomato sauces and tomato pastes have
been heated so they already have improved amounts of lycopene,” says Natasha
Murray, an accredited practicing dietitian based in the Northern Territory.
"Make a pasta sauce with canned or fresh tomatoes and that will also have
more lycopene than if you eat raw tomato."
However, she says, it's important to eat a
mix of raw and cooked vegetables as over-cooking can destroy other nutrients,
such as vitamin C.
Swap corn on the cob for canned corn
Scientists at Cornell University in the US
believe canned sweet corn may be healthier than corn on the cob. They say heat
processing boosts the amount of antioxidants called phenolics in corn. Cooking
corn at 115°C for 25 minutes increased the phenolic content by 32 per cent.
Canned
sweet corn
Researcher Dr. Rui Hai Liu says his
research shows that eating canned vegies is just as important as eating fresh
vegetables.
"It doesn't matter if it's raw, it
doesn't matter if it's cooked, it doesn't matter if it's fresh, it doesn't
matter if it's processed. You simply need to eat a variety of fruits and
vegetables to get maximum health benefits," says Liu.
Slow cook meat
While grilling and barbecuing are seen as
healthy ways to cook meat, the high temperatures can create chemicals linked to
cancer in animals. Dietitians say cooking meat at high temperatures forms
heterocyclic amines - linked to the development of colorectal, pancreatic and
breast cancers.
A National Cancer Institute study also
found that people who liked their beef medium to well-done increased their risk
of stomach’ cancer threefold compared to someone who had their beef rare to
medium-rare.
“We’ve known for a long time about
blackening meats that it’s not good for your ‘ says Melbourne-based dietitian
Terrill B. It’s better to cook meat for a longer time at a lower temperature so
the meat breaks j down and softens without the blackening’.
Eat potatoes cold
Once cooled, cooked potatoes and cooked
pasta contain more resistant starch, a type of fiber that improves bowel
health. The CSIRO says increasing our resistant starch intake may be an
important step in reducing bowel cancer In Australia. They recommend 20g a day.
“When resistant starch gets fermented by friendly bacteria in the bowel it
makes butyrate,” says Bruere. Butyrate helps kill potentially cancerous cells
in the bowel, so have a potato or pasta salad at lunch.
Once
cooled, cooked potatoes and cooked pasta contain more resistant starch
Cook carrot whole
Boil or steam carrots whole and cut them up
after they've been cooked and you'll get 25 per cent more antioxidants, say
scientists at Newcastle University. They found that boiling carrots whole
helped them retain more of an anti-cancer compound called falcarinol - the
naturally occurring ingredient that gives carrots their sweet flavor.
"Chopping up your carrots increases
the surface area so more of the nutrients leach out into the water while they
are being cooked," says researcher Dr Kirsten Brandt. By cooking them
whole and hopping them up afterwards you are locking in both taste and
nutrients, so the carrot is better for you all round."
Add avocado to your salad
Eating healthy fats with your salad boosts
the amount of carotenoids you absorb from the salad, according to research from
Ohio State University in the US. Carotenolds help fight disease and are mostly
found in colored fruits and vegetables, but the body needs fats and oils to
absorb them properly. “We found that about three to five times more carotenoids
were absorbed when study participants consumed a salad with avocados,” says the
study’s Dr Steve Schwartz. While olive oil has many health benefits such as
omega-6 fats which play an anti-inflammatory role, it’s not ideal for cooking.
“Olive oil has a low smoke point, which means its nutritional benefits are lost
at a lower temperature”, says Bruere. “There’s also some suggestion that
heating olive oil to high temperatures may lead to the formation of
carcinogens’ Seed and nut oils, on the other hand, have a higher smoke point so
can be heated to higher temperatures , while retaining their goodness.
Add
avocado to your salad
Add vitamin C to boost iron intake
Vitamin C can help your iron levels,
explains Bruere.”If you eat a boiled egg, have a glass of orange juice and
you’ll absorb more iron from the egg” she says. So add fruit to your cereal,
tomato to your sandwiches, and vegetables to your chicken or steak. “Wait 20
minutes after eating before having wine, tea or coffee, as the tannins in these
drinks stop Iron absorption adds Murray.
