Many Japanese also practice a several-hundred-year-old cuisine that may have contributed to the birth of Hara Hachi Bu, or at least made it easier to practice. It's called "kaiseki," and while it has various manifestations, it essentially involves starting a meal with vegetables and following them up with protein and then carbohydrate.

That style of eating allows you to eat less for reasons described in the next section, but the kaiseki style of eating is also scientifically smart. It improves insulin sensitivity and ameliorates an age-accelerating process called glycation, which, together, make it easier to get lean while also improving your chances of living as long as an Okinawan.

Before some Google-happy internet Hardy Boys out there research the term and call me on it, let me acknowledge that there are two types of kaiseki. One is a traditional multi-course meal often served as a feast that begins and ends with rice. The second originated as a frugal meal by Sen no Rikyu, the Japanese tea master from the 16th century. It's this second one that's the focus of this article.

The kanji (logographic) characters used to write the word kaiseki translate literally to "breast-pocket stone," and the concept comes from Zen monks who would put warm stones in the front folds of their robes to simulate the feeling of fullness and thereby ward off hunger.

While there are several variations of kaiseki meals, they typically start with some light soup or broth, followed by a vegetable dish and then a protein dish, and then concluded with a rice dish. This "one soup, three sides" concept wasn't just arbitrary, though.

The soup or broth set the tone of the meal. You'd start off slowly and patiently with a gut-friendly dish. It would also stifle any ravenous hunger you might be experiencing so you wouldn't wolf through the rest of the meal. Vegetables came next because of their fiber content; they would help your body to start to feel full and allow you to embrace the concept of Hari Hachi Bu.

Protein and fat came next, and then, when you were close to being 8/10ths full, came the invariably small portion of carbs.

While the rationale for the kaiseki style of eating sounds pragmatic, it's also got some science to back it up.

Back in 2017, Alpana Shukla and colleagues demonstrated that eating the protein and vegetable components (the patty, lettuce, and tomato) of a hamburger 10 minutes before eating the carbohydrate portion (the bun) led to far lower elevations of post-meal glucose and insulin levels.

Given that eating a hamburger that way is Bizarro-world unrealistic, Shukla, et al. conducted another "nutrient order" study, this time using a more realistic eating pattern.

They rounded up 16 subjects with type II diabetes. All 16 consumed isocaloric meals of the same macronutrient composition on three separate days, one week apart, after a 12-hour fast. The three meals were based on the following conditions:

1. Participants ate carbs first (ciabatta bread and orange juice) over a 10-minute period. They then rested 10 minutes before eating protein (skinless chicken breast) and vegetables (lettuce, tomato, and cucumber with Italian vinaigrette), again over a 10-minute period.
2. Participants ate protein and vegetables first. They began with protein and vegetables eaten over a 10-minute period, followed by a 10-minute rest period, and then finished off with the carbs (bread and orange juice), again eaten over a 10-minute period.
3. Participants ate vegetables first. Again, they got 10 minutes to finish the first course. They then took a 10-minute rest, followed by protein and carbs eaten over a 10-minute period.

All study participants had blood drawn just before mealtime and at 30-minute intervals up to three hours after the start of the meal.

Eating carbs last slowed down the insulin response as effectively as acarbose and nateglinide, two commonly used blood-sugar drugs.

Consuming protein and vegetables first resulted in the lowest postprandial glucose elevations, while eating only the vegetables first had the lowest insulin response, in addition to having a postprandial glucose response nearly as low as the protein and vegetable first strategy.

The researchers figured that reduced insulin response had to do with "delayed gastric emptying." More precisely, the fiber in the vegetables was acting like the nuclear reaction control rods in a nuclear reactor, which mirrors the concept behind the kaiseki style of eating.

A muted insulin response is certainly important for diabetics but keeping insulin/blood sugar levels from spiking too high after meals is also a useful strategy to keep non-diabetics slim, or to keep those who are borderline-diabetic from getting too close to the blood sugar precipice.

Shukla also found that eating carbs last reduced ghrelin, the hunger hormone, thereby suggesting that a kaiseki style, carbs-last meal might make you eat less when the next meal rolls around.

But this style of eating has another bonus, one that Shukla, et al. didn't mention.

You start life off with baby skin. You eventually end up looking like an old catcher's mitt. This is largely due to a chemical reaction known as glycation, which is simply the binding of proteins to sugar. It's virtually identical to what happens when you grill a burger.

It's also virtually identical to what happens in your body when you habitually keep blood sugar levels above what the medical profession considers to be the normal fasting range (70 to 99 mg./dl).

Once these blood sugar levels start to hover over 85 mg/dl – long enough, high enough, and often enough – glycation starts to be a problem. In other words, you start to "cook" yourself; you start aging prematurely and your face takes on the appearance of an old catcher's mitt way earlier than it otherwise might.

Not only does having perpetual high blood sugar cause you to slow-cook yourself, externally and internally, it also leads to a host of metabolic problems, including, but not limited to, insulin resistance and its hefty partner-in-arms, obesity.

Clearly, glycation is something you want to ameliorate, and the kaiseki style, carbs-last eating strategy likely would do that.

Clearly, the kaiseki style, vegetables and protein first, carbs-last strategy isn't going to work if you're eating a hamburger. You could, of course, dissect your hamburger and eat each macronutrient separately, but that'll cause people to shun you and whisper behind your back for the rest of your life.

However, given a normal, sit-down dinner situation, having your carbs last, while not necessarily ideal taste-bud wise, is pretty easy to do. Salad or non-starchy vegetable side dish first, followed by your meat course and finished off with your rice or potatoes or pasta.

I don't necessarily think that you have to eat ALL your vegetables before you have a bite of protein. I suspect you could achieve the same ends if you had a few forkfuls of vegetables and then had a bite or two of meat before going back to the vegetables. Neither do I think you need to emulate Shukla's protocol where you wait 10 minutes before starting to eat the next course; that isn't practical. It would also lead to that shunning thing I talked about.

Oh, and the soup that precedes the traditional kaiseki-style meal? It's nice but probably not necessary. If you do embrace that part of the tradition, don't make it a noodle or rice soup – broth or vegetable soup only.

The most important lesson to be learned from the kaiseki style of eating and Shukla's experiments is simply to eat your carbs last. This simple strategy could well allow you to stay insulin sensitive and keep your waistline trim, in addition to avoiding premature aging.

1. Okumura K. The Order in Which to Properly Eat Food, Inspired by Kaiseki-Ryori. Medium. Oct. 22, 2020.
2. Shukla AP et al. Carbohydrate-last meal pattern lowers postprandial glucose and insulin excursions in type 2 diabetes. BMJ Open Diabetes Res Care. 2017 Sep 14;5(1):e000440. PubMed.
3. Shukla AP et al. Food Order Has a Significant Impact on Postprandial Glucose and Insulin Levels. Diabetes Care. 2015 Jul; 38(7): e98-e99. PMC.
4. What is Kaiseki? Complete Guide to Beautiful Art of Japanese Cuisine. Japan Wonder Travel Blog. 2021/09/08.