Thursday, June 25, 2009

Kiwifruit as part of a healthy Singaporean Diet

I recently delivered a talk on Kiwifruit as part of a healthy Singaporean diet. This was conducted during the launch of the Zespri Kiwifruit season which will last till the end of the year. In general we Singaporeans do not eat enough fruits and vegetables. Just look at a plate of Char Kway Teow, Chicken Rice and Fishball Noodles. There is hardly enough veggies in each dish to make up even one serving!

Here are the salient points of the speech I delivered. Remember that you need at least 2 servings of vegetables and 2 servings of fruits everyday and one serving is equal to around 100gms or one cupful. So remember to eat more fruits and veggies!



Children and adolescents are not eating enough fruits and vegetables

Children are unable to eat as much as adults, yet their nutritional requirements are higher than adults. Adolescents are eating lots of junk food and snacks which are high in sodium, saturated fats and low in nutritional value.

According to a study by LaChance(1), Kiwifruit was ranked #1 amongst a list of 27 popular fruits in terms of nutrient density. That means that for children especially, every mouthful of kiwifruit carries more nutritional value than if he was eating other fruits.

Since an apple a day keeps the doctor away, let’s compare Kiwifruit with Apple to get a sense of the nutritional density of the fruit.


Table 1: Kiwifruit vs Apple in terms of nutrition density

It is not easy to get kids to eat fruits and vegetables, so we want to make sure that every mouthful counts. Eating Kiwifruit is a practical way of getting as much nutrients into kids as you can.

Eating fruits and vegetables need to be cultivated from young.

In Singapore, it has been shown that amongst the Chinese adults, those who were eating the recommended number of servings of fruits and vegetables were three times more likely to have cultivated the habit during childhood. (2)

An adequate intake of fruit during childhood may protect the person from getting cancer in adulthood. It has been shown that childhood intake of fruit and vegetables were inversely associated with the risk of cancer in adulthood. (3)

Children are finicky eaters especially when it comes to fruits and vegetables. But it is often easier for them to enjoy fruits as they are often sweet and tasty. My kids love Zespri Gold Kiwi. It is so easy to eat, you just need to cut in half and scoop it out. I don’t have to force them to eat it, in fact, they have to ask for permission to eat the last one in the fridge.
Childhood asthma in Singapore and Kiwifruits

Asthma affects one in five children in Singapore and is a growing problem. Kiwifruits are very high in Vitamin C and it has been shown that children with a diet high in Vit C have less wheezing episodes. Vit C is also very important to keep the body’s immune system healthy which can help lower the risk of getting infections like the H1N1 flu.(4)


Table 2: Nutrients in Kiwifruit
Source www.whfoods.com

Cancer and Cardiovascular Disease


Cancer, heart disease and stroke are the principle causes of death in Singapore, accounting for almost 60% of all deaths in 2007.5 Heart Disease

Heart Disease accounts for 28.5% deaths in 2007.(5) It is clear in the studies that consumption of fruit and vegetables can protect against coronary artery disease. (6)

Kiwifruit is high in folate which possibly lowers blood levels of homocysteine, which is a risk factor in coronary heart disease. The high levels of potassium contained in Kiwifruit is beneficial for lowering blood pressure. It is also high in antioxidants, phytochemicals and Vitamin E. These have all be suggested to be cardio-protective. However, it Is interesting to note that Vit E supplements by themselves has not been shown to lower the risk of coronary disease.(7) However, taken together with the other nutrients in the fruit like the antioxidants and phytochemicals, it exerts its protective effect. So in other words, it is still better to take a good diet of fruits and vegetables rather than swallowing supplements if you want to protect your heart!

Cancer

Cancer accounted for 27.7% of deaths in 2007.(8) WHO expert panel estimated that low fruit and vegetable intake contributes to 5 to 12 percent of all cancers, and up to 20 to 30 percent of gastrointestinal cancers that may otherwise be preventable.(9) The protective effect of fruits and vegetables has been noted especially in relation to cancers of the gastrointestinal tract. In Singapore, cancer of the colon and stomach account for 25.1%.

It has been reported that the low intake of vegetables is associated with the increase risk of colorectal cancer in Chinese adults. (10) The protective effect of fruits and vegetables comes from a combination of antioxidants, phytochemicals and dietary fibre found in fruits and vegetables. Kiwifruit is very high in soluble fibre. It is shown that regular intake of Kiwifruit can promote regular bowel movement.11 The combination of high dietary fibre, together with the antioxidative properties of Vit E, Vit C and phytochemicals found in Kiwifruit can contribute significantly to a healthy cancer prevention diet.

References:

1. Lachance P, 1997, Journal of the American College of nutrition

2. Ling AM et al. Defining and measuring stages of change for dietary behaviors: readiness to meet fruit, vegetable, and grain guidelines among Chinese Singaporeans. J Am Diet Assoc 2000; 100:898-904

3. Maynard M et al. Fruit, vegetables, and antioxidants in childhood and risk of adult cancer: the Boyd Orr cohort. J Epidemiol Community Health 2003; 57: 218-25

4. Francesco F et al, Consumption of fresh fruits rich in vit C and wheezing symptoms in children, Thorax 2000:

5. Source: MOH http://www.moh.gov.sg/mohcorp/statistics.aspx?id=5526

6. Ness AR et al. Fruit and vegetables, and cardiovascular disease: a review. Int J Epidemiol 1997;26:1-13

7. Yusuf S et al. Vitamin E supplementation and cardiovascular events in high-risk patients. The Heart Outcomes Prevention Evaluation Study investigators. N Eng J Med 2000; 342: 154-60


8. Source: http://www.nccs.com.sg/pbcation/canhelp/Dec05/focus1.htm

9. International Agency for Research on Cancer (IARC) Handbook of Cancer prevention. Lyon IARC, 2003

10. Seow A et al, Food groups and the risk of colorectal carcinoma in an Asian population. Cancer 2002;95:2390-96 11. Rush E. C. et al. Asia Pac J Clin Nutr. 2002, 11;164-8

Acknowledgments

This article is based on materials presented in the Dietary Guidelines for Children and Adolescents for the Healthcare Professional, Health Promotion Board 2007

5 comments:

Anonymous said...

Hi Dr Tay:

After eating kiwi (green type),my throat and even my noise get itchy,I wonder why?is it i have some allergy reaction to kiwi fruit?

ieat said...

Yes some people have a mild allergy to Green Kiwifruit. Sounds like you do.

Anonymous said...

is there a diff between golden kiwi and the green kiwi?
or they both deliver the same nutrients.

ieat said...

They are almost the same. The Green has more fibre than the Gold and the Gold is slightly higher in Vit C. But by and large almost similar.

Rocket Girl said...

I really love the golden kiwi. The green kiwi is actually quite sweet if you let it ripen....