Saturday, October 30, 2010

Nutrition transition in South Korea: a unique case

Last semester, when going through a newspaper article about foreign foods with one of my more advanced classes, I was surprised to find out that most of the students had not tried any of the foreign food discussed in the paper, even with some foods coming from places as close to Korea as China or Japan. This was shocking to me; I wouldn’t say Seoul, one of the biggest cities in the world, is lacking in the foreign food department. In the areas with a high concentration of foreigners, there is a wide variety of international cuisine, and even in the more “Korean” neighbourhoods, you can’t walk a block without passing a “Dunkin’ Donuts”, a “Paris Baguette”, and a “Pizza School” (not exactly international cuisine, but definitely indicative of Western influence). Yet, despite this international presence, most of the students seem to stick to a pretty traditional Korean diet for the majority of their meals, cooked by their traditional Korean stay-at-home moms.

When I asked a student how often he ate Western food, he told me that it is rare for him or his family to eat it. It is only on special occasions that they might have a Western meal at Outback Steakhouse or one of the other foreign restaurant chains, something I found slightly surprising considering the number of Western-style restaurants in Seoul.

This led me to wonder…

How does South Korea manage to maintain such a traditional diet in an increasingly globalized world?

And this, in turn, led me to the concept of nutrition transition.

Nutrition transition definition

A nutrition transition is something that happens in middle and lower-income countries as they develop and become more industrialized. Cities grow and begin to offer imported foods from industrialized countries. Unfortunately many of these foods are heavily refined, high in added sugar and saturated fat and low in fiber (1). In other words, it is a shift to, essentially, the “Western diet”, resulting in malnutrition from a lack of high-quality nourishment as well as obesity.

This used to only happen in developed countries, but now it is taking place in developing countries as well. Malnutrition that was once signaled by emaciated bodies is now affiliated with obesity. The change in diet is accompanied by a shift in disease patterns from communicable diseases to chronic diseases (2). All in all, a transition from a traditional diet to a Western diet is never a good thing.

Traditional diet → Western diet = malnutrition + obesity + chronic disease

Although, South Korea modernized a lot earlier than most other Asian countries, its nutrition transition patterns stand out from the rest of Asia. After recovery from the Korean War (1950-1953), South Korea’s economy grew rapidly, and with this growth came the introduction of components from the Western diet, such as fast-food restaurants, which became popular with the younger generation (3).


The studies I looked at examined changes in diet, obesity and overweight, as well as disease and mortality that reflect the nutrition transition in South Korea. I will outline the major trends below. It should be noted, however, that the data was taken from 1995 and 1998 Korean National Health Surveys. Unfortunately, in some areas, I couldn’t find anything more recent because the statistics are in Korean, but I have supplemented the findings of the older studies with recent data where available.

Diet: high in vegetables, low in fat

The studies I looked at highlighted a large increase in animal food products, (meat in particular), and a decrease in cereal intake, (principally rice), in South Korea during the nutrition transition. Rice remained the most consumed food, followed by kimchi (see “Oh holy kimchi” for more info!) (3).

Plant foods, including fruits and vegetables, are central in a Korean diet, with a daily vegetable intake of 280 grams per capita, which is among the highest in Asia (4). Recent surveys show that this large vegetable intake has increased even further in recent years to almost 336 grams per day in 2005, which is remarkable considering this rise is the opposite of what is normally seen in a nutrition transition (5).

The other most notable trend is concerning fat intake. The daily per capita fat intake has more than doubled from 16.9 grams in 1969 to 41.5 grams in 1998. Although this represents a considerable increase, the proportion of energy that Koreans get from fat is still significantly lower than other Asian countries (3).

Currently, contribution of fat to total energy remains below 20% as is recommended by Korean nutritionists (6). One theory regarding the low fat intake is that it can be linked to Korea’s high carbohydrate consumption, which makes up a large portion of total energy intake. Carbohydrate intake has not declined rapidly in South Korea as it has in other developing nations. Another theory relates to Koreans’ method of cooking which involves using only small amounts of sesame-seed oil (7).

Obesity/overweight rates: low but problematic

Rates of obesity are markedly low in South Korea, but rates of overweight are quite a bit higher. In 1998, rates of obesity in adults were 1.7% for men and 3.0% for women (3), and ten years later, in 2008, data indicated that 4.0% of Korean men were obese versus 3.6% of Korean women (8). Rates of overweight in 1998 were 24.3% for men and 23.5% for women (3). Data from 2001, just three years later, shows overweight statistics of 29.6% in adult men and 25.9% in adult women (this is the most recent data I could find) (9).

Although rates of both obesity and overweight have increased, prevalence of obesity in South Korea is much lower than in Western countries, and also lower than that of other Asian countries as well (3). Overweight is a bit more of a problem, however (more to come on this…).

Disease and mortality: a late transition

Disease patterns in South Korea have shifted from communicable diseases to non-communicable diseases, as is the norm in a nutrition transition, but this shift occurred in the 1970s, compared to the 1940s in the United States and 1950s in Japan. The rate of death from infectious and parasitic diseases (per 100,000 people) decreased from 23.2 people in 1985 to 11.7 people in 1999 (3).

Today, Koreans continue to maintain a relatively low level of non-communicable diseases compared to other countries of similar economic development (6).

“Sin-To-Bul-Yi: A body and a land are not two different things”


“Sin-To-Bul-Yi” is a concept promoted in South Korea that means a person should eat foods produced in the land in which he or she was born and is living. This is just one of many movements to retain the traditional diet in Korea. These methods range from TV programs promoting local food to the government putting on workshops to train the public in traditional cooking methods (7). The Korean Dietetic Association (KDA) also plays a large role in publicity and education. They provide nutrition services, hold seminars, monitor food and nutrition information in the media, and distribute educational materials, among other things (3).

Despite the internationalization that has occurred in South Korea, fat intakes have not increased to the extent that they have in other countries, nor have obesity rates, thanks, in part, to huge efforts on the part of the Korean government and other associations. This case is an exception to the usual cases of nutrition transition that have occurred around the globe.

It would be valuable for other Asian countries, (and any country, really), to examine South Korea’s tactics in the hope that they too can prevent the remnants of their traditional diet from slipping away, at the inestimable expense of their health.

Sources

(1) Popkin B. 2010. What is the nutrition transition? http://www.cpc.unc.edu/projects/nutrans/whatis. Access date: October 5, 2010.
(2) Wikimedia Foundation Inc. 2010. Nutrition transition. http://en.wikipedia.org/wiki/Nutrition_Transition. Access date: October 5, 2010.
(3) Lee MJ, Popkin BM and Kim S. 2002. The unique aspects of the nutrition transition in South Korea: the retention of healthful elements in their traditional diet. Public Health Nutrition 5(1A): 197-203.
(4) Kim SW and Popkin BM. 2000. Reply to salt consumption during the nutrition transition in South Korea [letters to the editor]. Am J Clin Nutr 72: 199-201.
(5) Lee JS and Kim J. 2010. Vegetable intake in Korea: data from the Korean National Health and Nutrition Examination Survey 1998, 2001 and 2005. Br J Nutr 103 (10): 499-506.
(6) Kim CI. 2010. The Korean Experience: Dietary Transition. www.who.or.jp/AHP/docs/200409/abstract3.pdf. Access date: October 27, 2010.
(7) Kim SW, Moon SJ and Popkin BM. 2000. The nutrition transition in South Korea. Am J Clin Nutr 71: 44-53.
(8) Organisation for Economic Cooperation and Development. 2010. OECD Health Data 2010. http://stats.oecd.org/Index.aspx?DatasetCode=HEALTH. Access date: October 27, 2010.
(9) Cho SJ, Ministry of Health and Welfare. 2002. Nutrition Overview – Republic of Korea. www.wpro.who.int/internet/resources.ashx/NUT/kor.pd. Access date: October 27, 2010.