Prof Grant Schofield takes a look at this research paper, published in the Journal of Atherosclerosis, on the effects of protein – the forgotten macronutrient – and the difference that protein can make.



The study is centred around the protein leverage theory – the idea that humans will eat until they get enough protein and they will no longer be hungry.

Is good quality protein in reasonable amounts going to end up better for humans compared to lower protein diets? A cool thing about this study is they have what’s called a graphical abstract, which you’ll see below.



This tells us that they’ve done a meta-analysis of trials. They’ve taken 54 studies and put them together. That’s the highest form of evidence on the hierarchy of evidence. We’ve got two different exposures – lower protein diets, between 10-23% of calories coming from protein, compared with higher protein diets, with 20-45% of your calories coming from protein.

So, how do the people who are exposed to the higher protein diets fare compared to the people who are exposed to the lower protein diets? What are the outcomes? The outcomes are:

  • Weight loss
  • Fat mass
  • Systolic blood pressure
  • Total cholesterol
  • Triglycerides
  • Fasting insulin

And we can see pretty reasonable effects in this meta-analysis.

About a 10-20% improvement across all of those variables, the biggest being a 20% reduction in triglycerides, and then weight loss and fat mass being about a 10% reduction. So, people exposed to the same studies, but eating the higher amount of protein fared a lot better, which is really a good thing in favour of the protein leverage hypothesis.

So, get some good quality protein, eat it up, satisfy your needs, and carry on.


Learn more

Take your nutrition knowledge to the next level. Prof Grant Schofield and Dr Caryn Zinn are the lead instructors in the Certificate in Advanced Nutrition

The Certificate in Advanced Nutrition:

  • is designed to give you a university-level education in nutrition at a fraction of the cost.
  • gives you a solid foundation in the science and practice of nutrition including low-carbohydrate and keto diets, fasting, weight loss, gut health and allergies.

Learn more here.