What Should We Eat To Promote A Longer Life?

Amidst the enormous advice, claims and counterclaims by the modern dietary world, it seems impossible or at least difficult to come to an answer to this question, and it probably is. We have got pure veganism that promises to cater to our biosphere and help with gut issues, to unchecked carnivory-that is closest to what our ancestors had.

A segment of the book– How The World Really Works, by Vaclav Smil, helps us look at this question in an obvious but atypical way.

To find the least riskiest diet, those associated with life expectations above 80 years with least possible complications, we not only ignore all of the dubious dietary claims on the internet, but also, surprisingly, scientific journals. Scientific studies and their metastudies have repeatedly failed to produce consistent clear-cut outcomes because of the holes and gaps in data collection from the masses and other factors. Most people find it difficult to decide what they should eat. Asking one simple question can give us a headstart to our answer.

“Which populations live the longest and what their diets are?”

Japan has had the highest average longevity since the early 1980s, when it's combined (male and female) life expectancy at birth surpassed 77 years. By 2020, Japan’s combined life expectancy at birth was about 84.6 years. Women live longer in all societies, and their life expectancy in Japan was about 87.7 years in 2020.

Average longevity is an outcome of complex and interacting genetic, lifestyle, and nutritional factors. Trying to find out to what extent it is determined by diet alone is impossible, but if there are unique features to a nation’s diet, they clearly deserve a closer examination.

Traditional ingredients consumed in Japan in substantial quantities differ only subtly from those eaten or drunk in abundance in neighboring Asian nations.

The Chinese and Japanese consume different, but nutritionally equivalent foods. China’s average life expectancy in 2020 was 78.08 years.

Similarities between Chinese and Japanese ingredients

These are not differences in nutritional quality, but merely matters of appearance, colour, and taste. The Japanese diet has undergone an enormous transformation during the past 150 years.

• Before 1900, the diet consumed was insufficient to support the population’s growth potential and it resulted in shorter stature.

• The consumption of milk, first introduced at school lunches to prevent malnutrition, began to rise, and white rice became abundant.

• Seafood supply expanded rapidly as the country built the world’s largest fishing fleet.

• Meat and baked goods emerged as favourites in this traditionally non-baking culture.

Higher incomes and hybridization of tastes brought increases in mean blood cholesterol levels, blood pressure, and body weight—and yet heart disease did not soar and longevity increased.

Latest published surveys show Japan and the US to be surprisingly close in total food energy consumed per day.

Similarities and differences in the consumption of the listed macros in Japan and the USA

Something noteworthy is that sugar and fat consumption in the US is very high.

The widespread availability of ingredients, and easy access to cooking instructions and recipes on the internet means that you too can, minimise your risk of premature mortality and start eating à la japonaise—be it the country’s traditional cuisine.

But before that, let us see what the best European model of diet and longevity is. The Spanish women are the runners-up in the world’s record life expectancy.

The country traditionally followed the so-called Mediterranean diet, with high intakes of vegetables, fruits, and whole grains complemented by beans, nuts, seeds, and olive oil. After the average incomes in Spain rose, they rapidly changed those habits to a surprisingly high degree. Until the late 1950s, Spain continued to eat very frugally–diets were dominated by starches and vegetables; meat supply and actual consumption was unimaginably less. Sugar consumption (about 16 kilograms in 1960) was high in relation to other foodstuffs.

Dietary changes accelerated after Spain joined the EU in 1986, and by the year 2000 it became Europe’s leading carnivorous nation. The way Spain now eats is substantially different from the way Japan feeds itself—and, most definitely (being the continent’s top carnivore), this diet hardly resembles the frugal, near-vegetarian, and life lengthening legendary Mediterranean diet.

• It consumes twice the mean meat consumption of the Japanese.

• The Spanish supply of animal fat is four times the Japanese rate.

• Spaniards now consume almost twice the volume of plant oils as the Japanese—but their consumption of olive oil is about 25 percent lower than in 1960.

• Since 1960, per capita consumption of sugar has doubled and it is now about 40 percent above the Japanese level.

• Spanish wine-drinking has been relentlessly declining.

But despite a more meaty, fatty, and sugary diet (and also rapidly abandoning drinking its supposedly heart-protecting wines), Spain’s cardiovascular mortality has kept on declining and life expectancy has been rising. Since 1960, Spain has added more than 13 years to its combined (male and female) longevity prospect, raising it from 70 to more than 83 years by 2020. This is just one year less than in Japan.

So of the meat lovers, the question is- Is one additional year of life worth replacing half of the meat you eat with tofu? And if you love the taste of tofu, THERE YOU GO!

These are truly personal decisions to make—but the conclusion is reasonably clear. If we were to stake longevity (accompanied by healthy and active life) solely on the prevailing diet— then Japanese eating has a slight edge, but an only slightly inferior outcome can be brought by eating as they do in Valencia.

One thing to remember is that more than anything, our genes have a lot of influence on various things related to our bodies. Surrounding environment also has a great impact on longevity and overall health. The fact is that our body has an impressive tolerance mechanism, that's why the Spaniards are doing great with their diet.

But few obvious observations are-

• Excessive sugar and fat consumption directly affects wellbeing and hence longevity (the US and Japan comparison).

• Moderate consumption is worth more than restricting certain food groups.

Let me know your thoughts below in the comment section.