Intermittent Fasting vs. Regular Caloric Restriction

Today I would like to talk about the difference between caloric restriction at every meal and Intermittent Fasting. Especially in regards to the question which strategy is more feasible as a long term strategy to extend lifespan.


Research indicates that caloric restrictions leads to an efficient metabolism and a slowed aging process. This can either be achieved by general caloric restriction or by a restricted feeding window, also called intermittent fasting. Both ways should lead to a decrease in caloric intake. And finally it should be made clear that this article is evaluating the pros and cons of these approaches in the light of life-long caloric restriction. In short term many things might work if the goal is just fat-loss. For long-term compliance more aspects need to be considered.

one or two large meals per day
Do you prefer large meals...


Intermittent Fasting

In my experience a shortened eating time during the day is not enough to ensure such a caloric restriction. I find myself quite capable of eating a big amount of food in one meal. Therefore attention to caloric intake still has to be paid. With that said let’s discuss the advantages and disadvantages of this approach:

Advantages:


  • Less time spend preparing food and eating
  • With fewer meals, one can eat to greater satiety after the meal
  • Therefore, in theory, a caloric deficit is easier to achieve
  • Feelings of hunger are compressed into one fasting window
  • Hormone-release during the fasting period leads to increased fat utilization
  • Easy to tailor around social eating events
  • The relationship with food will be revealed (e.g. emotional eating)

Disadvantages:


  • Challenging for some people to get all the required nutrients in one or two meals per day
  • Once appetite is used to eating bigger meals it takes time to go back to several smaller meals
  • Hunger or rather the feeling of an empty stomach might be an issue for some people




regular small meals
... or regular but smaller meals?

Regular Caloric Restriction

With regular caloric restriction I assume three meals a day and a mainly or almost exclusively plant-based diet. Plant-based eating has been shown to have life extension properties on it’s own if done correctly. A healthful diet includes only whole foods and should make caloric restriction easier because of increased satiety. Here are the Advantages and Disadvantages of this approach compared to intermittent fasting:

Advantages:


  • Smaller meals are easier to digest and assimilate leading to higher nutrient absorption
  • Easier to plan even sized meals
  • Regular eating might reduce hunger in some people
  • High amount of vegetables can (needs) to be eaten at every meal to ensure satiety – this also leads to the advantage of high nutrient-density of the diet
  • Higher intake to healthy high fiber foods possible

Disadvantages:


  • Lower satiety at each meal, "the need to stop before satisfied"
  • Harder to adjust to social eating (when portion sizes in restaurants are bigger)
  • Might not fit some peoples schedule
  • Meal preparation might be necessary



In the end it is a matter of preference. But just make sure to give each approach a decent trial period before you judge it. Your body has to adjust either way. Give it at least 30 days on each protocol.
In my next article I will discuss how I go about it and combine fasting with regular caloric restriction to reap benefits of both approaches.