Vitamin C - Myths and Facts (Part 3)

HOW MUCH VITAMIN C DO YOU NEED?
The amount of vitamin C you need depends on your age, gender and other factors, such as smoking pregnancy. Below is the Dietary Reference Intakes for vitamin C:

 

Infants
•0 - 6 months: 40* mg/day	•7 - 12 months: 50* mg/day
*Adequate Intake (AI)
Children
•1 - 3 years: 15 mg/day	•4 - 8 years: 25 mg/day
•9 - 13 years: 45 mg/day
Adolescents
•Girls 14 - 18 years: 65 mg/day	•Boys 14 - 18 years: 75 mg/day
Adults
•Women age 19 year and older: 75 mg/day	•Men age 19 and older: 90 mg/day
Pregnant Women
•14 - 18 years: 80 mg	• Over 18 years: 85 mg
Breastfeeding Women
•14 - 18 years: 115 mg	•Over 18 years: 120 mg

Smokers or those who are around secondhand smoke at any age need an additional 35 mg per day. For most people, a healthy and balanced diet should provide an adequate amount of vitamin C you need, so there is no need to take excessive vitamin C supplements.

References:

1. http://ods.od.nih.gov/factsheets/VitaminC-QuickFacts/
2. http://www.nlm.nih.gov/medlineplus/druginfo/natural/1001.html  
3. http://www.nlm.nih.gov/medlineplus/ency/article/002404.htm
4. http://edis.ifas.ufl.edu/pdffiles/FY/FY21500.pdf
5. http://www.aoa.org/x11814.xml
6. http://ods.od.nih.gov/factsheets/vitaminc
7. http://www.nlm.nih.gov/medlineplus/ency/article/002145.htm
8. http://www.umm.edu/altmed/articles/vitamin-c-000339.htm
9. http://lpi.oregonstate.edu/infocenter/vitamins/vitaminC/index.html

Vitamin C - Myths and Facts (Part 2)

WHAT ARE THE EFFECTS OF VITAMIN C ON HEALTH?

Vitamin C has been claimed to have a lot of functions, some of them have been proved by scientific studies, but some of them are still questionable. Here are some commonly claimed effects of vitamin c on human’s health.

The Common Cold

Although vitamin C has long been believed to cure the common cold, research shows that for most people, vitamin C supplements do not reduce the risk of getting the common cold or cure the cold after getting it. However, people who take vitamin C supplements regularly might have slightly shorter colds (about 1 day shorter in duration) or slightly milder symptoms. Using vitamin C supplements after cold symptoms start does not appear to be helpful.

Antioxidant

In the body, vitamin C acts as an antioxidant. It helps to protect cells from the damage caused by free radicals, which are formed when your body breaks down food for energy. People are also exposed to free radicals in the environment from cigarette / tobacco smoke, air pollution, ultraviolet light from the sun and radiation. The buildup of free radicals can cause aging and may possibly cause cancer and heart disease.

Cancer Prevention and Treatment

Many population based studies suggest that people with regularly high intakes of vitamin C-rich foods might have a lower risk of getting cancer, such as skin cancer, cervical dysplasia, lung cancer, colon cancer or breast cancer. On the other hand, the foods rich in vitamin C also contain many other beneficial nutrients, so it is difficult to determine the role of vitamin C in preventing cancer. Moreover, vitamin C supplements do not seem to have any effect on preventing cancer.
In addition, it is not clear that taking large doses of vitamin C will cure cancer or help cancer treatment. Also, some doctors are concerned that large doses of dietary vitamin C supplements may interfere with the chemotherapy medications and radiation therapy for cancer.

Cardiovascular Disease

People who eat lots of fruits and vegetables seem to have a lower risk of cardiovascular disease. However, it is still unknown that whether vitamin C is the one that helps prevent cardiovascular disease, such as heart attack or stroke. Vitamin C itself doesn’t lower cholesterol levels or reduce the overall risk of cardiovascular disease, but it may help protect arteries against oxidative damage. Some studies suggest that vitamin C may prevent the progression of hardening of the arteries and the build-up of plaque, which can cause heart attack. Even though the relationship between vitamin C and cardiovascular disease is not very clear, studies suggest that people with low levels of vitamin C may be more prone to have a heart attack, stroke or peripheral artery disease. Still, there is no evidence to prove that taking vitamin C supplements will help or cure these conditions.

Age-related Macular Degeneration (AMD) and Cataracts

AMD and cataracts are two of the leading causes of vision loss in older people. Some researchers do not believe that vitamin C affect the risk of getting AMD. However, research suggests that vitamin C combined with other nutrients might help keep early AMD from worsening into advanced AMD. Some other researchers believe that a combination of vitamin C, zinc, beta-carotene and vitamin E may benefit people who have advanced AMD.

Taking vitamin C higher than 300 mg/day for a number of years may have a protective effect on cataracts. However, a 7-year controlled intervention trial demonstrates that there is no relationship between vitamin C intake and cataracts prevention or progression. Like other claimed health benefits, more research is needed to clarify the relationship between vitamin C and AMD/cataracts.

Collagen Synthesis

Collagen is an important protein and structural component of blood vessels, tendons, ligaments, and bone. Our body requires vitamin C to make collagen. It is also needed to help wounds heal and sometimes used in anti-aging products.

Other Benefits

Vitamin C helps our bodies absorb iron from plant-based foods and helps the immune system work properly to protect the body from disease. Some studies also suggest that taking vitamin C along with vitamin E may help prevent pre-eclampsia (a common cause of premature births) in women who are at high risk. Vitamin C may also reduce effects of sun exposure, such as sunburn or redness.

References:

1. http://ods.od.nih.gov/factsheets/VitaminC-QuickFacts/
2. http://www.nlm.nih.gov/medlineplus/druginfo/natural/1001.html  
3. http://www.nlm.nih.gov/medlineplus/ency/article/002404.htm
4. http://edis.ifas.ufl.edu/pdffiles/FY/FY21500.pdf
5. http://www.aoa.org/x11814.xml
6. http://ods.od.nih.gov/factsheets/vitaminc
7. http://www.nlm.nih.gov/medlineplus/ency/article/002145.htm
8. http://www.umm.edu/altmed/articles/vitamin-c-000339.htm
9. http://lpi.oregonstate.edu/infocenter/vitamins/vitaminC/index.html

Vitamin C - Myths and Facts (Part 1)

WHAT IS VITAMIN C?

Vitamin C, also known as ascorbic acid, is a water-soluble nutrient. Some animals can make their own vitamin C in their bodies, but human beings have to get this nutrient from food and other sources. Vitamin C is a necessary nutrient for normal growth and development. Your body can only absorb a certain amount of vitamin C depending on your age, gender and other factors. The excessive portion which can’t be absorbed will leave the body with urine.

HOW CAN YOU GET VITAMIN C?

You can get vitamin C through various sources, such as natural foods and dietary supplements. However, you need to remember that getting vitamin C through natural foods is much better than taking supplements. Among all the foods, fruits and vegetables are the best choices.

The following is a list of foods which are rich in vitamin C:

• Citrus fruits and their juices, such as orange, lemon, grapefruit and lime.
• Other fruits, such as kiwifruit, mango, papaya, pineapple, strawberry, cantaloupe and watermelon.
• Vegetables, such as red pepper, Brussels sprouts, broccoli, cabbage, cauliflower, baked potato, tomato and spinach.
• Other than naturally occurring vitamin C, some foods and beverages are fortified with vitamin C, such as certain cereals. You can find that information on the product labels.

Dietary supplements typically contain vitamin C in the form of ascorbic acid, but there are other different forms of the vitamin C supplements available, such as sodium ascorbate, calcium ascorbate, and other mineral ascorbates.

The vitamin C content of food may be reduced by prolonged storage and cooking. Since vitamin C is water-soluble, cooking food in water, such as boiling, may lead to vitamin C losses as well. Steaming or microwaving may be better ways to retain vitamin C in food. Fortunately, many fruits and vegetables are usually eaten raw, which allows people to get a good amount of vitamin C out of them.

References:

1. http://ods.od.nih.gov/factsheets/VitaminC-QuickFacts/
2. http://www.nlm.nih.gov/medlineplus/druginfo/natural/1001.html  
3. http://www.nlm.nih.gov/medlineplus/ency/article/002404.htm
4. http://edis.ifas.ufl.edu/pdffiles/FY/FY21500.pdf
5. http://www.aoa.org/x11814.xml
6. http://ods.od.nih.gov/factsheets/vitaminc
7. http://www.nlm.nih.gov/medlineplus/ency/article/002145.htm
8. http://www.umm.edu/altmed/articles/vitamin-c-000339.htm
9. http://lpi.oregonstate.edu/infocenter/vitamins/vitaminC/index.html

Four Quick Health Tips for Your Thanksgiving Dinner

1.         Talk More, Eat Less

Thanksgiving is the great time for family and friends to get together. Every day we are busy with our own stuff, so it’s a great time for you to catch up with your loved ones. Chatting with people at the Thanksgiving dinner table not only helps you get social, but also healthy. When you talk, you slow down with eating, and it gives your brain time to detect your fullness and let you stop eating. When you eat slowly, you’ll get a chance to enjoy great flavors than just stuffing yourself to maximum capacity with all the food.

2.         Light Food Goes First

Turkey is a must and stuffing is appealing. However, try to fill yourself up with lighter dishes first, such as salad and veggies. Sweet potatoes have a great mixture of fiber and vitamins, and a pinch (just a pinch and no butter needed) of brown sugar makes it delicious. When you have a good food base in your stomach, you won’t clean up your plate in seconds like a storm.  Instead, you can slowly enjoy all the great flavors melting in your mouth. 

3.         Go for Sweets, YES!   

Instead of trying to find reasons to persuade yourself from desserts, I say go for it.  BUT, keep portion control in mind, it is the key. A small piece of pie, a scoop of ice cream or a small bowl of chocolate pudding won’t kill you. You probably have been waiting for them for a long time. Have some but limit it to a small portion. Other than that, remember to have some coffee along with your desserts. A study showed that caffeine generates a greater thermic effect, which increases energy expenditure, basal metabolic rate and fat oxidation.¹   At the same time, caffeine acts as a central nervous system stimulant and reduces the sleepiness after turkey consumption.

4.         Move Around after a Meal

After your great meal, take a 15 to 20-minute walk. Walking after a meal helps you increase your metabolism and burn off any excess calories from the meal. If you don’t like walking by yourself, ask your family and friends, or even take your pets to join you. You are helping them stay healthy too! If you still feel walking is too boring for you, then do something else. Help clean the table, put away stuff, do the dishes or take out trash. There is always something better to do than just sitting down and watching TV.

1. Westerterp-Plantenga. Green tea catechins, caffeine and body-weight regulation. Physiology & Behavior. 2010; 100 (1): 42–46.