I have spoken to many people about food in Japan, whether is about breakfast, lunch, special food, shabu shabu (almost a winter broth) or even snacks and everyone I have spoke to said the same thing: watch the salt.
As this is the month of awareness, let’s take a look at the problems salt, along with other causes, may bring. Welcome to cardiac problems in Japan.
Firstly a definition. Cardiac problems will consider heart disease, heart attacks and cardiovascular disease as well. If this were to be published anywhere else I would have to think about each problem separately but not too many people would be interested in that, do let me know if I’m wrong on that front.
Starting off in a happy place, cardiac issues is one of if not the main causes of death in Japan, like many other highly developed nations. There are many causes for this, not just McDonald’s and fast food. The WHO have ranked 3 heart related conditions as the main causes of death in Japan which were: Ischaemic heart disease (aka Coronary Artery Disease), Aortic aneurysm, and other cardiovascular disease.
However, there have been 42,300 fewer CHD deaths because of medical and surgical treatments from 1980- 2012.
Major health trends
To start with let’s take a look at some general health trends which have contribute towards higher levels of heart disease in Japan. Firstly, Japan has become increasingly Westernized and has been since the 1960’s. While this has had many advantages culturally, economically, socially etc, there has been a negative impact on health.
The major trends that have been seen in Japan are a rise in the number of smokers within Japan, a noticeable difference in BMI- levels are much higher (in 1980, the average BMI for men was 22.5 kg/m^2 and by 2000 this has risen to 23.4kg/m^2); a rise in the number of diagnosed diabetics; an increase in blood pressure.
Side note: blood pressure. Blood pressure has 2 values: a systolic value (the top number) and a diastolic value (the bottom number). The WHO recommends that one’s BP should be 120/80 mm Hg- which is the ‘perfect’ value. High blood pressure is any reading that at rest is over 130/80 mm Hg.
Japan’s blood pressure is worrying- the average systolic blood pressure is 135 mm Hg (which is high) and the mean diastolic reading is 85 mm Hg. This average 135/85 mm Hg puts you into the Hypertension stage 1 category or High blood pressure stage 1 group.
Major factor: salt
One resource I used during my research was the Cardiovascular Risk Assessment Chart by Dietary Factors in Japan (which is a brilliant resource- linked in further information) and the major risk assessment was salt.
Salt is essential to life as we cannot naturally product it but we need it in moderation only. In the UK, it is recommended to have no more than 6 grams of salt a day- the recommended daily limit in Japan is 1.5 grams of salt (which explains why Japan has a lower level of CDV (cardiovascular disease). However, daily recommended limits are not always possible.
Average daily salt intake (from a sample size of 9115 people) was 14.0±5.2 g. This means that the lowest average daily intake was 8.2g. The risk assessment categorizes people into 2 groups based on salt intake high (men and women that consumed more than and including 8g and 7g of salt respectively) and low (those who consumed less than this).
This risk assessment showed that after 29 years, there had been 1070 deaths attributed to CVD. From the 2 salt intake groups, there were 57 deaths from the low salt intake group and 1,013 deaths from the high salt intake group (while there were other factors which contributed to their deaths- numbers are telling).
What factors have contributed towards Japan’s low CVD death rate?
Strangely enough, the Japanese diet has helped (and hindered) CVD in Japan. The main things which can reduce risk is consuming omega 3 (eating fish or rarely via supplements), avoiding sugar (hard to do in Japan), avoid trans fats (again difficult to do), ensure adequate vitamin D intake (either dietary, by being in sunlight or supplements) and controlling iron.
Not surprisingly, the Japanese consume a lot of fish- but the amount the Japanese consume has dropped. In 2016, the Japan Times reported that the average fish consumption as a mean 27.3 Kg a year- which is still a massive amount.
Additionally, the Japanese diet of high levels of fish, fruit, vegetables and (ideally) low salt consumption are the perfect heart diet. However with higher salt consumption and what can only be described as a fast food diet (low vegetables, fruit and fish), CVD is extremely likely and possible.
Soy based products (tofu) are also extremely helpful in reducing CVD risk and its’ benefits have been noted in men and women but especially in post-menopausal women.
CVD is regional in Japan and it has mostly been reduced except in major urban areas (Tokyo and Osaka). In major urban areas, there are higher levels of stress, less time to cook (so more processed food), less time for exercise etc so there are higher levels of CVD.
Further reading- The Japanese heart foundation (JHF)
There is certainly more information on this topic- in English (more research papers than advice) and in Japanese. The best resource I have found was the JHF or Japanese heart foundation (BHF or AHF anyone?).
The JHF have information on diet, research, AED and first aid training and so much more. Please do check it out- there are enough info-graphics that if you have a good scientific mind, you should be okay.
Thank you for reading and happy exploring.