SuttaCentral

Intermittent Fasting vs. OMAD


#1

mn65: “Sir, I’m not going to try to eat my food in one sitting per day.
mn65: For when eating once a day I might feel remorse and regret.”

In MN65, the Buddha admonishes Venerable Bhaddāli, who is having difficulty eating one meal a day (OMAD). I personally sympathize with Venerable Bhaddāli given my own ongoing adventure with eating only before noon, given that OMAD is simply too radical for me now.

With intermittent fasting, one eats in one part of the day, usually in a 6-hour interval. Although many choose to eliminate breakfast, I chose to eliminate dinner according to the EBTs.

mn70: You too should abstain from eating at night.
mn70: Doing so, you’ll find that you’re healthy and well, nimble, strong, and living comfortably.”

What happened? Well, I gradually returned to the weight I had when I got married decades ago. I also became chilled more easily, so I just started wearing a hat and kept warm. And my sleep was untroubled by digestion. OK. :white_check_mark:

But I have trouble eating enough for the day. And I certainly can’t eat it all in one sitting. My stomach simply can’t hold that much food. I guess I’m inefficient. So OMAD is definitely not possible for me currently and I’d be like Venerable Bhaddāli, having to apologize to the Buddha for breaking OMAD every day. And that’s ok, since I am not a monk and have not actually taken up the OMAD rule.

Given my struggle with not being able to eat enough, I was curious enough about what was going on that I attached a glucose monitor to myself (hey! I’m a cyborg now!). I wanted to understand more about what was going on in my body. And this is what I saw:

What I saw was that my blood sugar spiked dangerously at breakfast. Those of you with diabetes will recognize the beginnings of a hyperglycemic spike at 6am, at breakfast time. :scream_cat:

You’ll also notice that the spike plummeted drastically shortly after onset. What happened? What did I do?

I exercised. Nothing vigorous, just enough to raise heartrate and increase depth of respiration. Those were enough to absorb the start of a hyperglycemic spike and cancel it out. And that experience made me understand the benefits of OMAD. :thinking:

With OMAD, one does not eat in the morning, certainly not at 6am. Instead, one moves about and gets the body going again with activity for several hours before eating. :open_mouth:

And because of this, I’ve re-aligned my intermittent fasting with OMAD by refraining from eating too early. As a result, I no longer have blood sugar spikes. :grinning:

For those of you fasting intermittently, you might wish to consult with your doctor and bring up this point about morning activity.
:pray:


#2

May we see an “after” graph? I’m curious to see what exercise before a slightly later OMotD looks like.

Thanks for the science! :robot:


#3

Armed with the prior day’s experience of glucose spiking, today I resolved to do things differently by doing the following:

  • upon arising, perform slow, through exercise to increase respiration and heart rate. A combination of walking around the room with eyes closed and hanging from a horizontal pole proved effective. Hypothesis: increasing metabolic rate prepares body for ingestion of fuel.
  • drink two glasses of water. Hypothesis: liquid in the intestines can initiate digestive processes and provide fluid required for diffusing nutrients across cell membranes.
  • eat something and chew thoroughly (e.g., english muffin with butter and fruit spread). Hypothesis: intestine needs something to work on.
  • stay active and do morning chores. Hypothesis: increased circulation needs time to establish itself and chores need to get done anyway
  • perform some light mental activity for a while. Hypothesis: the brain itself needs warming up.
  • start breakfast after being awake an hour or two. Hypothesis: the body is now ready for most efficient consumption of food and will not spike on glucose.

Here is today’s chart:

Compare with yesterday’s chart and you’ll see a remarkable improvement at staying within the green band. For the curious, walking meditation happened from 12-1, during which time glucose was stable and low. The two morning “mountains” are from eating. The first was the “warmup food”. The second was a full bowl of oatmeal with nuts, dried fruit and linseed oil. Interestingly, lunch happened just before noon prior to walking meditation. Notice a tiny afternoon peak that smooths out into an hour of walking meditation.


#4

This makes Mae Chee Kaew’s schedule of starting the day with a bunch of walking meditation make even more sense to me. Are you going to try it without the pre-food and even doing OMAD? I appreciate the data.


#5

Have you tried playing with the allowable tonics? Oil, raw sugar, salt?
From what I have witnessed in Thailand forest monks usually have some of these tonics in one form or another around 2-3pm in the form of coffee or tea/infusion added by sugar.
Then, they work around the place, sweeping, fixing stuff, etc and some, before the evening, even have another round of tea, fruit nectar, etc. Note that even some even have little snacks like sunflower seed, pickled myrobalan, etc
Also, the latter in life you change habits the harder it may be for the body to adjust, isn’t it?


#6

:face_with_raised_eyebrow:
That must be hard!


#7

It is quite good actually. In Thailand you can buy from the little shops you find along the highways to southern province. They cal it luk-samooh-cheh-ihm


#8

What you have observed is the Dawn Phenomenon, an early morning (4am - 6 am) surge in blood sugar levels due to the effect of various counter regulatory hormones such as Cortisol. It can occur even in normal people (but a pre diabetic status should be excluded).
Light Early morning exercise is a good way to absorb the extra glucose floating around in the blood (as you found by experimentation!).
{ Light exercise is aerobic causing the muscles to burn glucose, thereby lowering the blood glucose. Heavier exercise is anaerobic, there is a deficit of glucose created by the excess muscular activity, causing the liver to secrete even more glucose, hence raising the blood sugar.}

If we closely examine the Buddha’s schedule, a similar pattern of doing walking meditation (aka light exercise) at the time around dawn (4 am - 6am) is seen:-

SN10.8

Then the householder Anāthapiṇḍika went to the Cool Grove and approached the Buddha.

Now at that time the Buddha had risen at the crack of dawn and was walking meditation in the open. He saw Anāthapiṇḍika coming off in the distance. So he stepped down from the walking path, sat down on the seat spread out, and said to Anāthapiṇḍika, “Come, Sudatta.”

AN3.16

After rising, in the last watch of the night, while walking back and forth and sitting, he purifies his mind of obstructive qualities.

SN 4.7

He spent most of the night practicing walking meditation in the open. At the crack of dawn he washed his feet and entered his dwelling. He laid down in the lion’s posture—on the right side, placing one foot on top of the other—mindful and aware, and focused on the time of getting up.

When a person first takes up intermittent fasting, the body is not used to running at the lower blood sugar level, the levels of counter regulatory hormones are still high, even as the average insulin level has dropped as food consumption has decreased. This could account for the early morning spike as seen in your case, as the liver dumps glucose to the blood after a prolonged time of fasting to maintain the average blood sugar level.

The treatment for Dawn phenomenon, is (surprise surprise!) more intermittent fasting and a lower carb diet.

What can you do to avoid the Dawn Phenomenon? Get the excess sugar out of the liver, and improve insulin sensitivity. Ok, how do you do that? Reduce your carb; specifically eliminate sugar, sugary drinks, potato chips, white flour (white bread, pasta, etc.), and other refined & packed foods. An LCHF diet or intermittent fasting… Or preferably both.

As the pre existing liver stores get used up over time and the level of counter regulatory/ Stress hormones settle, the blood glucose tends to run lower and remain more stable.

So, unless there is a health condition, intermittent fasting is likely to prove beneficial in the long run in reducing the overall blood glucose, as well as the levels of Stress hormones such as Cortisol and norepinephrine. This likely contributes to the feeling of being light and energetic as described by the Buddha.

“Mendicants, I eat my food in one sitting per day. Doing so, I find that I’m healthy and well, nimble, strong, and living comfortably. You too should eat your food in one sitting per day. Doing so, you’ll find that you’re healthy and well, nimble, strong, and living comfortably.”

Disclosure: I’m a practicing Physician with a daughter who has Type 1 Diabetes and is on insulin with 24x7 blood glucose monitoring…hence the interest in the topic. This is just ‘my two bits’, it isn’t a substitute for a professional medical opinion - everyone should get that from their own health team, before embarking on any diet/ exercise regime (Duh!).


#9

I’m going to try to moderate my food input so it’s more consistent. Instead of a meail, I will eat continuously over a given set of hours to avoid gorging, which I find leads to drowsiness (i.e., food coma). The intestines are literally a pipeline and pipelines prefer steady input. We get the best mileage in cars when we stay at a constant speed without pumping the gas pedal. So I’m abandoning the concept of meal as too restrictive and simply being mindful to eat constantly during “the time to eat”. In this way the “meal” lasts hours and hours, but happens once a day.

I think our modern mindset of “meal-on-the-go” has contorted the notion of a meal, turning it into an exercise of stuffing food rapidly down our throats. My glucose monitor is telling me emphatically that such rapid eating is NOT good.

I have high blood pressure so salt is bad. I have adopted dark chocolate for medicine, and a few ounces helps a lot each day. Pure sugar is very spikey and bad. I suppose I could also have a spoonful of oil. I hadn’t thought of that. Thank you.

The body and habits adjust according to need and the glucose monitor has been very informative

:open_mouth: Fascinating! Thanks for all the information. :man_cartwheeling:

For morning exercise what I have found best is walking meditation with eyes closed. Having eyes closed requires moving the arms and it requires continuous careful movement with weight on one leg. Additionally, it requires an alert brain attentive to surroundings. This results in deep breathing as well as increased aerobic metabolism as you mentioned.

:walking_man: :sunglasses: :pray:


Above is the spike of a single banana eaten at 530AM. Closed eye walking meditation starting at 555AM. The exercise is extraordinarily effective within 10 minutes and absorbs the peak at 600AM.


#10

A very interesting post, friend Kabir. Thanks for this!


#11

…and thanks @karl_lew for the original post. Good stuff.


#12

I’m also finding that the first few bites of a meal do actually matter quite a lot in affecting glucose. The spikes you saw above are from a…banana. Typically I eat a banana first thing to break my fast. And that may not be the wisest thing.

Bananas, especially yellow bananas generally provide a blast of energy that can easily upset digestion and overwhelm metabolism with a glucose spike. Eating protein or fats (e.g., nut butters) simultaneously can flatten out the glucose spike and provide a gentler uptake in glucose. This is why desserts are eaten last. But even with main meals, perhaps eating all mashed potatoes first might not be advisable for those seeking to avoid glucose spikes. Eating fats and protein along with carbohydrates can moderate glucose spikes.

Here is today’s chart. I ate one teaspoon of almond butter with each bite of banana over two hours. It’s startling in that there is no glucose spike, just a gentle and gradual uptake of nutrients. I started eating at 5:38 AM. I will now heed my food intake much more mindfully!

So not only do we have to be mindful about time:

AN4.58:3.1: Yo saññatānaṃ paradattabhojinaṃ,
AN4.58:3.1: Carefully giving food at the right time,

We also have to mindfully give the right food. If we put a banana in an alms bowl, also put in protein and/or fats.

:pray: