Better Body Clinical Nutrition


How much food do I need, what is the right portion size for me

Tuesday, November 16, 2021 3:45 PM

Here is an article about the Nutritional tool called portion size.  Even though it is a simple concept this can be one of the hardest things to figure out.  It is variable (it changes) based on how much movement, the amount of protein, carbohydrates, and fat within the food as well as the nutrient needs of the body.  There is how fast your body breaks down food as well, called metabolism.  This can be fast, slow or anywhere in between.  Think about it, have you known someone who ate whatever they wanted and still looked skinny, or someone else that didn’t seem to eat very much, but had a harder time with weight?  

This article points out that metabolism tends to slow down as we age, so what a person needs at 16 is different than what they need at 40.  So to make this concept as simple as possible it is best to look at trends.  If you are increasing in weight then that is an indication that either the metabolism is slowing down and therefore a reduction of portion size might help turn that trend around, while a decrease in weight could mean to increase the portion size.  This of course depends on if a person is at the proper weight in the first place.  So you see how it can get confusing.  

Here is another example, lets say you are losing weight, but your weight is more than it should be for you, well in this case you wouldn’t want to increase the portion size because you are getting closer to your goal weight.


The best tool for this is something called BMI (Body Mass Index):

Body mass index (BMI) is a common tool for deciding whether a person has an appropriate body weight. It measures a person’s weight in relation to their height.

According to the National Institutes of Health (NIH)Trusted Source:

  • A BMI of less than 18.5 means that a person is underweight.
  • A BMI of between 18.5 and 24.9 is ideal.
  • A BMI of between 25 and 29.9 is overweight.
  • A BMI over 30 indicates obesity.

So going back to making this an easy tool, here is the best place to start:

1. Check your height and weight and use the calculator on this page to look at your BMI (there are fancier more precise ways to do this, but this is a good start)

2. If the BMI is less than 18.5 increased portion size might be a good idea, but working with a Nutritionist to find the right balance for you might be a good option.

3. If the BMI is between 18.5 and 24.9 then this is an indication that your doing well with the portion size you are eating, so keep it up :)

4. If the BMI is above 25 then this is where a reduction of portion size can be a tool torwards getting to your ideal weight.