Protein foods and weight loss…

Recently I was invited to an event where I was asked to speak about Natural Yoghurt and protein levels in our food. I often get asked about the benefits of protein in the diet and it’s health impacts, and it became clear to me at the event, that many female members of the audience avoided foods which made ‘protein rich’ claims, as they felt it was a nutrient only important for bodybuilders and gym-goers.

Firstly it’s important to point out that protein deficiency in the UK is VERY rare. The National Diet and Nutrition survey shows us that generally protein intakes are above the Reference Nutrient Intakes (RNI) in all age and sex groups¹.

However foods rich in protein certainly can have their benefits, especially for someone trying to lose weight or maintain a healthy weight. I often recommend clients have protein at breakfast, especially those who I know are likely to get hungry early on during the day. The reason for this is that the scientific evidence suggests that protein-rich meals increase our feelings of satiety following a meal. This means that we feel ‘fuller’ for longer after a meal high in protein than we would if we ate, say a carbohydrate or fat-rich meal.

Image(²).

What are the benefit of satiety?

The image² above shows the difference between satiety and satiation and the effect that both of theses can have on our food intake. Research also shows us that protein has a long-term effect on satiety and on our levels of satiation at the end of a meal.  Increasing our ‘fullness signals’ after a meal, may help us reduce the calories we consume from food throughout the rest of the day. Protein may therefore also help reduce the likelihood of craving foods or the need to top-up your energy levels mid-morning or mid-afternoon by prolonging that feeling of fullness.

What’s the reason behind protein’s satiating effect? Honestly we still don’t fully know but the current research suggests it’s likely to be some or all of the ideas below (³, 4):

• A greater decrease of Ghrelin (a hormone which stimulates appetite) after protein and carbohydrate ingestion than after fat ingestion
• Protein stimulates dietary-induced thermogenesis (process of energy production in the body caused directly by the metabolising of food consumed) to a greater extent than other macronutrients

And…

• Favouring retention of fat-free mass (muscle) at the expense of fat mass, which in turn increases the body’s metabolic rate

So topping up on protein at mealtimes (especially breakfast, in my opinion) can be a good way to keep you feeling “fuller for longer” after a meal. Below are a list of some protein rich foods both from animal based and non-animal based sources.

Non-animal based proteins:

Nuts (including nut butters)

Seeds

Beans

Lentils

Pulses

Quorn

Tofu

Quinoa

Soya products

Animal based proteins:

Milk

Eggs

Yoghurt

Cheese

(good quality) Meat

Fish

References:

1. Henderson L, Gregory J, Irving K, Swan G. National Diet and Nutrition Survey: adults aged 19 to 64 years. Volume 2: Energy, protein, carbohydrate, fat and alcohol intake. London: TSO, 2002.
2. http://www.nutrition.org.uk/attachments/146_1.%20Bridget%20Benelam%20Introduction%20to%20satiation%20and%20satiety.pdf
3. http://ajcn.nutrition.org/content/87/5/1558S.long
4. http://www.sciencedirect.com/science/article/pii/S0924224414002386