Eating Well Boosts Your Immunity

With cold and flu season upon us, certain nutrients such as vitamin C, zinc and selenium are often touted by some to provide protection against seasonal illness. While it's true that these nutrients do boost the immune system, more is not better! "Almost all vitamins and minerals play some role in ensuring an optimal immune response," says Catherine Field, registered dietitian and spokesperson for DC, "but high doses do not help and may do harm."
Here are the 'straight goods' based on evidence provided by dietitians – your trusted source for food and nutrition advice:
Vitamin C
The Facts: Optimal vitamin C status has been identified as important for the immune cells involved in defense against viruses. The main functions of vitamin C are to help heal cuts and wounds; keep gums, teeth, and bones healthy; keep blood vessel walls strong and help absorb iron from the foods we eat. Despite being studied for over 40 years, there is insufficient evidence to advise taking more vitamin C to prevent colds or the flu. The Recommended Daily Allowance [RDA] is 75 mg for women and 90 mg for men (an additional 35 mg should be added for smokers). This is easily obtained by having 1-2 servings of vitamin C rich citrus fruits (such as oranges), or vegetables like sweet peppers and broccoli. Vitamin C is also added to a number of foods that are routinely consumed by Canadians, such as apple juice. A higher dose of vitamin C is not without side effects such as causing digestive problems.
Zinc
The Facts: Zinc is important for the cells involved in defense against viruses. Zinc is also involved in many bodily functions. It supports normal growth and development during pregnancy, childhood and adolescence. It is also required for a proper sense of smell and taste so that low zinc status can influence your appetite and enjoyment of food. The current RDA for zinc is 8 mg for women and 11 mg for men. The best sources of zinc are seafood, meat, seeds, cooked dried beans, peas and lentils. A serving of beef (75 g or 2 ½ oz) provides approximately 4.6 mg of zinc and a serving of lentils (175 mL or ¾ cup) provides almost 2 mg of zinc. Plant sources are less reliable as the level of zinc in plants depends on the content in the soil. As a result, vegetarians who mainly depend on plant sources of nutrients are advised to consult with a dietitian to insure their needs are being met.
Selenium
The Facts: Although selenium is important for a healthy immune system, there is little evidence of a deficiency in the Canadian population or evidence that consuming selenium supplements will reduce the risk of viral infections. Recommended amounts are small, only 55 micrograms daily for adults, readily obtained from nuts, seafood, organ meat, pork and whole grains. Half a cup (125 mL) of cooked brown rice provides 8-10 micrograms of selenium and a serving of mixed nuts (60 mL or ¼ cup) has about 150 micrograms of selenium.
Feed a cold and starve a fever? Not good advice!
The Facts: Viral infections, such as the flu, are often associated with a fever. However, there is no evidence that "starving a fever" by reducing the amount of food eaten will reduce a fever. In fact, a fever is a helpful means used by our own immune system in order to fight off the viral infection. If we stop eating, the immune system doesn't work as well and all of the nutrients mentioned above, as well as many others, are important to the immune system. "While it may be tempting to eat less when you're feeling unwell, try to eat smaller, more frequent meals and healthy snacks to support your body's defenses and drink plenty of water," says Field.
Source: http://www.dietitians.ca/news/media.asp?fn=view&id=14102&idstring=

Prenatal Nutrition Workshops

Come to an informative and interactive workshop on the newest nutritional guidelines for pregnant women!

Topics include:

• fish, mercury and omega-3 guidelines
• iron and calcium supplements and food sources
• fibre and constipation issues
• food safety guidelines including the safety of herbal products
• caffeine recommendations
• and more!

Your choice of location:

South Delta: Oct 14, 2009. 7-8pm. $20. Suite 202-1624 56th St.
Vancouver: Oct 21, 2009. 7-8pm. $25. 680B Leg In Boot Square.

Please RSVP

Upcoming Event

Healthy, Happy Eaters

A Nutrition Talk about the little ones: 6 months – 2 years

• Introduction of solid foods: what, how much and when
  
• Signs of readiness to introduce solid foods
  
• Infant food preparation methods and recipes
  
• Family meals and how to avoid conflicts about food
  
• Healthy snack ideas
  
  

Thurs, July 30, 2009. 7:00-8:00pm

Video at 7:00pm followed by information session and Q&A

By donation (recommended donation of $20)

Please RSVP

PMS

Premenstrual syndrome (PMS) is a common condition experienced by women in the 2 weeks prior to menstruating. Symptoms of PMS include bloating, weight gain, tender breasts, headaches, back or abdominal pain, food cravings, and a lack of energy. Other signs include irritability, anxiety, tension, aggression, and feelings of being unable to cope or loss of control.

Vitamin B 6 (pyridoxine) may be beneficial to women with PMS. Results from a study examining nine published trials representing 940 patients with PMS showed that doses of Vitamin B 6 up to 100 mg/day as a supplement may be of benefit in treating premenstrual symptoms and premenstrual depression. The recommended intake for Vitamin B 6 for premenopausal women is 1.3 mg/day. It's important not to exceed the safe upper limit for Vitamin B 6 which is 100 mg/day for non-pregnant women. High doses of Vitamin B 6 can cause neurological symptoms such as sensory neuropathy (e.g. tingling or numbness in hand or feet).

Many other types of dietary supplements including magnesium, and Vitamin E have been advocated for the reduction of certain symptoms of PMS but further research is needed in this area. Calcium supplements (1000-1200 mg/d) have demonstrated significant benefit in a large, rigorous, double blind, placebo-controlled trial but more studies are required. The efficacy of various herbal supplements including evening primrose oil for PMS is uncertain because of a lack of consistent data from scientific studies.

The general recommendation for PMS is to eat well, keep active, manage stress, and get plenty of rest.

Source: Dietitians of Canada. 2003 National Nutrition Month Campaign. Healthy Eating...Tasty and Easy. Finding Solutions to Women's Nutrition and Healthy Eating Challenges. Resource Manual for Health Professionals p.32.

Upcoming Event

Eating for Two!?!

If you are pregnant or planning on it...
...come to a relaxed and informative nutritional workshop!

Topics will include:

• fish, mercury and omega-3 guidelines
• iron and calcium supplements and food sources
• fibre and constipation issues
• food safety guidelines including the safety of herbal products
• caffeine recommendations

Time: June 20, 2009. 10:00-11:00am.
Location: Suite 202 – 1624 56 Street Delta, BC V4L 0A2
Cost: $20
Refreshments will be served.

Please RSVP 

Fibre

Recently I have had a number of conversations about fibre. Not only about preventing/relieving constipation but also about the fact that Canadians’ average intake of fibre is only about half to two-thirds of the recommended intake. The lack of fibre in one’s diet as well as a number of other reasons, such as iron supplements, some medications and the hormone changes during pregnancy, can lead to constipation.

The best things you can eat to prevent/relieve constipation are wheat bran, oat bran, whole grains, psyllium (fibre in some cereals and Metamucil), prunes, prune juice, beans, and lentils. Also, the amount of food you eat is a factor. The more food you eat, the less likely you are to be constipated; the best way increase the quantity of food you eat is to load up on fruits and vegetables because these tend to be lower calorie items and they have some fibre too!

Some other foods that contain specific kinds of starches or fibre that help keep you regular are potatoes, bananas (they can’t be too ripe), carrots, parsnips and rutabagas. There is also some evidence that exercising can help keep you regular and some compounds in coffee may help too.

As for all the hype about yogurt keeping you regular – this has not been proven by any research studies. The bacteria in yogurt may be beneficial to keep the bacteria in your digestive system normal but don’t expect yogurt to help prevent constipation.

Give your new high-fibre diet a two week test period! You may experience some temporary bloating and gas but your digestive track will adapt. Eating a high-fibre diet will help keep you regular but it also can help to control diabetes, blood cholesterol, and possibly prevent some cancers.

One last thing to note: when eating more fibre, drink more water!


References:
HealthLink BC File #68l, October 2007. “Managing Constipation in Adults”. http://www.healthlinkbc.ca/healthfiles/hfile68l.stm

Nutrition Action Healthletter: Centre for Science in the Public Interest. Exit Strategy: How to Stay Regular. March 2009.

Spinach

Over the last couple of weeks, I have been watching the spinach in my vegetable garden sprout from seeds and grow into tiny plants. My vegetable garden is 4 feet by 6 feet, so I only have room to grow a few select vegetables. Spinach made the short list not only because it can be grown in the early spring – surviving some frost and even a snow fall – but also because it is an amazing vegetable from a nutritional perspective. Spinach is an excellent source of vitamin A, vitamin K, folate, vitamin C and magnesium. It is also a good source of fibre, vitamin B2, and vitamin B6.

One hundred grams of fresh spinach (about 1 ½ cup packed down) provides as much calcium as 1/3 cup of milk (which doesn’t sound like much but that’s pretty impressive for a vegetable!) and as much iron as 100 grams of cooked ground beef. The amount of iron in spinach is particularly notable even if it is not as well absorbed into the body as the iron found in meat. One can increase the absorption of iron from spinach by eating it along with something containing vitamin C, such as mandarin orange slices, strawberries, or even by putting lemon juice in the salad dressing!

I am looking forward to the day when the spinach in my garden is ready to harvest!

Chocolate

Happy Easter! Along with this weekend being a very important religious holiday, this time of the year has an intimate relationship with chocolate. When our children think of Easter the first thing that often comes to mind is the chocolate they will receive. Chocolate is everywhere! In every store one enters there are mounds of chocolate waiting to be bought and consumed.

If you have begun to think that chocolate is a health food, think again! The reason some of us are lead to believe that chocolate is healthy is the fact that cocoa contains compounds called flavonoids which have antioxidant properties. These flavonoids that are found in cocoa are indeed healthy and can help reduce one's risk of developing cancer and heart disease.

The problem is that the common milk chocolate that is widely available and given/received at Easter is not just cocoa. The cocoa has been processed and this not only reduces the amount of flavonoids found in the chocolate but now the processed chocolate contains unhealthy levels of saturated fat, sugar and calories. In 35g of milk chocolate (just over an ounce) there is about 10 grams of fat or more, most of which is saturated, and 180 calories. This is half a day’s worth of saturated fat and a tenth my calories for the day - all in a few mouthfuls!

So while you pop this type of bite-sized morsel into your mouth, think about it. And next time maybe reach for the dark chocolate with a higher percentage of cocoa to satisfy that chocolate craving. At least you will be consuming more flavonoids and less sugar than milk chocolate. More of the good stuff and less of the bad – isn’t that what we all strive for?


References:

Ki Won Lee, Young Jun Kim, Hyong Joo Lee, and Chang Yong Lee. Cocoa Has More Phenolic Phytochemicals and a Higher Antioxidant Capacity than Teas and Red Wine. J. Agric. Food Chem., 2003, 51 (25), pp 7292–7295

http://www.cbc.ca/news/background/health/chocolate.html