Thursday, 29 October 2009
A nutrition lecturer at the University of Worcester is encouraging people to think more about their diet, as the second wave of swine flu begins to hit Britain.
Dr Laurence Trueman said certain foods could help to stimulate your immune system, enabling you to fight off such infections more efficiently.
“Many people are concerned about the predicted swine flu pandemic,” he said. “Although there is probably very little we can do to stem the spread of the disease, you can make slight modifications to your diet that will help your body be more proactive in fighting off the infection. Your immune system, like any other organ, needs to be fed.”
Dr Trueman explained that when the body becomes inflamed due to illness, the amino acid glutamine, a major food source for the immune system, can become limiting.
“The simplest way to boost your supply of glutamine is to eat foods rich in protein,” he said. “Science is now catching up with what mothers have known for centuries; chicken soup should be high on the menu for those suffering from colds and flu.” Other good sources of protein include meat, especially turkey and cod; and pulses and beans.
Dr Trueman said foods high in refined sugar have been shown to inhibit parts of the immune system. “Chocolate bars and sports drinks may help us feel better, but they don’t help us get better” he said, “And the worst culprits are often your morning cereals; ironically the good old English breakfast maybe is a far better choice when you’re ill, particularly if you grill instead of fry and place eggs, mushrooms and tomatoes at the top of list.”
Dr Trueman said good nutrition could also have positive effects on the virus itself. “Most viruses mutate quickly in the body resulting in your immune system having to deal with a fast moving target,” he said. “Vitamin C can slow this mutation process down, helping your immune system to get on top of the situation faster.”
Many people are aware that vitamin C is beneficial for cold and flu, but Dr Trueman said most people were unaware that vitamin C is effectively cleared from the blood by the kidneys every 4-6 hours, so regular consumption is necessary. Foods rich in vitamin C include oranges, blackcurrants, broccoli, sprouts and unsweetened fruit juices.
Dr Trueman added: “If you intend to take a high dose vitamin C supplement always seek medical advice if you are pregnant or have other medical conditions; and ladies be aware that large doses of vitamin C can compromise the action of the contraceptive pill.”
In general any foods that are rich in antioxidants will help suppress the virus mutation, but also help limit the damage done to the body. Such foods include all fruits and vegetables, but particularly onions, apples and tea that contain high levels of quercetin, an antioxidant that is targeted to the lungs; an organ that suffers badly during a bout of flu.
Dr Trueman explained that because the virus infects the upper respiratory tract, one of the major symptoms is the production of copious mucus that can leave the body dehydrated. “It is thus really important to stay hydrated by drinking plenty of water or decaffeinated drinks; particularly if you are suffering in a centrally-heated building,” he said.
All of Dr Trueman’s advice is in line with the characteristics of the Mediterranean diet, widely believed in the field of nutrition to be the optimum diet for promoting human health and longevity.