What is the purpose of not eating after noon?

Please read Bhaddaali-Sutta MN65 describing the laying down of the rule about not eating at improper times.

The sutta also contains the parable of the Ajaniya horse. An excellent tamed mule schooled by an expert trainer and put through the various stages of training, becomes endowed with ten qualities. Such a thoroughbred horse is fit to be regarded as a treasure by a king. Similarly, a man who has developed the Noble Eightfold Path and obtained right knowledge and right deliverance, becomes the richest field in which the seed of merit may be sown.

http://www.wisdompubs.org/book/middle-length-discourses-buddha/selections/middle-length-discourses-65-bhaddali-sutta

http://tipitaka.wikia.com/wiki/Bhaddali_Sutta

although to my knowledge this view isn't attested for anywhere, i think this custom has also an aspect of inculcating a sense of moderation, modesty and knowing one's limits in getting free rides

the monastics obtain their meals for free as donations, just one meal is a great gift and act of generosity, because lay people aren't obliged to feed monastics

expecting to be fed for free trice a day for instance would be impudent of monastics as it would put more strain on the lay community resources

The purpose is ideally for those who meditate were the extra food is more than what is appropriate.

Specialists must claim what they claim for active people who use up substantial energy on defilements and don't meditate much.

I could be wrong but it seems to me that often the majority of specialists, at least those whose religion is material science, are incorrect. They are biased by materialist views IMO.

I feel not eating after noon is a very good way to be healthy. The health problems happen when, even though one doesn't eat after noon, one has tea and other things, which by themselves are fine, but when taken with sugar, are bound to cause problems, given the fact that insulin sensitivity decreases as the day progresses.

It also doesn't go with the general advice that eating thus would help us be equanimous when struck with hunger. I prefer only water after noon, and even when I eat a huge meal during the day, it's all slow carb. Eating thus also helps to balance our body processes, as our body is catabolic during the day (hence eating mostly then to balance out, as digestion and assimilation is anabolic).

I also feel that the Budhha, who was so in tune with his feelings, could feel this last point, that eating this way leads to a balanced body at all times. Of course, no one way is the best, it's all about being on the middle path, right? But these, in my opinion, are some ways in which this diet, when done properly, could be helpful to us, as validated by the science of today.

Avoid too much food is sila.

Less food=Good health.

Good health=sukha.

Sukha is base of samatha.

Samatha is base of vipassana.

There are sila samadhi panna.

In my opinion it's best to eat mostly in between the time period of a few hours before sunrise and noon, to be in synch with the sun. As it is rising, it's generating energy and light until it's apex at noon, then gradually tapers down to sunset, as natural human activity should.

I think it's likely that there were cultural and situational factors influencing this meal schedule, like others have mentioned.

One thing might have been that, at the time this was begun, there may have been less food overall for that population. Eating less might have been easier because there was not much more food to eat. There wasn't much temptation. They didn't live in a state of perpetual plenty like many people in many countries now.

Just a thought.

Many people think of this is a sort of moderate asceticism. However, reading the suttas and doing additional research I came to realize that the actual purpose of this practice is to maximize health and well-being. According to Indian Ayurvedic medicine, which was in its heyday during the lifetime of the Buddha, the digestive fire or agni is maximal during the waxing of the sun, i.e., from sunrise to noon, and it is during this time that food should be taken to maximize digestion and assimilation of nutrition. It has nothing to do with asceticism, although of course the Buddha did teach that one should eat moderately, i.e., only what is necessary for good health.

I asked about this matter to my teacher before, a lot of thai monks have problems with their health because of eating once a day. Then i realised that a lot of them ate rice cakes and thai foods is not good for stomach if you don't eat rice. A lot of factors.

As for me, I've been taking the meals once a day before noon since 2015 and since then i feel fresh, lighter and i could meditate as long as i want because i don't have to think about having a lot of meals. I did medical checkup a few months ago and my health conditions are very good.

I guess you just need to balance your consumption and you'll stay healthy.

And also few years back, my japanese friend sent me a link about a doctor who'd been doing this once a day meal. His face from 20 years back and the current shows that he's getting younger and he did show up on television.

Eating once or twice a day has been shown to be very healthy and is called "intermittent fasting". It is especially useful for mental clarity and promoting the body's use of fat for energy, actually eliminating hypoglycemia rather than promoting it.

This state is called ketosis (not to be confused with diabetic ketoacidosis) and it has a profound impact on the brain, energy and cognition. It is being employed today in everything for aiding in the treatment of cancer, fueling ultra-long distance atheletes, reversing or greatly improving type 2 diabetes and treating brain injuries and conditions.

It and the teaching to eat temperately undoubtable has great benefit for meditation practices. Ever tried meditating with a food coma. Its like the reason for abstaining from alcohol. Its all about what is useful and helpful to one's practice.

The Buddha also advised avoiding things like onions and garlic due to their supposed effect on one's meditation practice.

ps

If you have been relying on many small meals it is due to getting most of your energy from carbohydrates. People who prefer a carb based diet may want to look at something like a "slow-carb diet) which eliminates sugar and refined grain in favor of slower absorbed carb sources like beans and oats that give a more even, longer lasting energy.

In addition to the answers already provided which are quite accurate, one minor point that occurs to me is culture.

For a long time in India yogis ate only one meal a day, even among Hindus.

The saying is a yogi eats one meal a day, a commoner eats two meals a day and a sick man eats three meals a day.

Kitagiri Sutta

I have heard that on one occasion the Blessed One was wandering on a tour of Kasi with a large community of monks. There he addressed the monks: "I abstain from the night-time meal.1 As I am abstaining from the night-time meal, I sense next-to-no illness, next-to-no affliction, lightness, strength, & a comfortable abiding. Come now. You too abstain from the night-time meal. As you are abstaining from the night-time meal, you, too, will sense next-to-no illness, next-to-no affliction, lightness, strength, & a comfortable abiding."

I agree that it's hard to eat only one meal a day. Even though there's a benefit of 'lightness' after some time hunger can become trouble.

If I am to chime in and add to the other answers.

If you are a meditator not eating after noon is not a problem.

1. You will be calming your bodily fabrication which reduces metabolism (let alone food, you will require less oxygen)
2. When you are looking at the arising and passing away of phenomena, you will see hunger is also such a sensation, constituting of large number of Kalapas. Practicing equanimity to fabrication mean that after some time you can be equanimous towards hunger too.

Also following Q&A may be of relavence: What dietary practices are most helpful for reaching enlightenment?

Eating after noon would also entail:

• go for alms round depriving time and effort ideally put for meditation
• excessive eating can lead to lethargy
• craving for the taste or eating can be a hindrance

I too am finding that small meals every 3-4 hours helps me meditate easier. Teachers like Ajahn Chah http://en.wikipedia.org/wiki/Ajahn_Chah have talked about not eating after 11am or noon. But he later developed diabetes and went into a coma for a year. Diabetes often is started by huge swings of blood sugar in hypoglycemia. That is why regular meals with protein (milk, tofu, yogurt, beans or meat if that is part of your diet) can help stabilize blood sugar and make diabetes a less probable outcome. In Thai monasteries with novices, they eat an early meal and then 11:30 eat the leftovers from the first. http://www.thaiworldview.com/bouddha/bouddha3.htm There were reasons why monks ate only in the morning - to make sure eating does not interfere with meditation is the reason given http://www.buddhapadipa.org/dhamma-corner/buddhist-tasks/ another practical reason is that the kitchen staff would not be able to participate at all in the afternoon or evening ceremonies if they had to cook many meals a day. There were definite reasons why that was chosen for centuries before, but what worked for another time and culture might be less effective today.

From my understanding, the Buddha laid down the rule to not eat afternoon in order to reduce the burden on the laity and to help the sangha avoid a negative reputation.

In the Latukikopama Sutta (MN 66) the Buddha said that there were many disadvantages to going for alms at night.

that monks wandering for alms in the pitch dark of the night have walked into a waste-water pool, fallen into a cesspool, stumbled over a thorn patch, or stumbled over a sleeping cow. They have encountered young hooligans on the way to or from a crime.