How much is too much protein?

Is there such thing as too much protein in healthy snacks? Forming a better understanding about nutrition with Form Nutrition

As with most nutrition questions, the answer is more complex than you’d imagine when you start to dig deep. At Lifebox, our mission is to provide healthy snacks that fuels the body, and protein plays a massive role in that process. We were lucky enough to catch up with Form Nutrition to discuss the pros and cons of high protein consumption:

The simple answer is that in a single dose, about 0.5g per kg body weight is probably a sensible upper limit. Long term, there is no evidence of kidney or other organ damage, or effect on mortality with high protein intakes.

That doesn’t mean to say an excessively high protein diet isn’t bad for you – rather, no studies have been conducted to prove it is (or isn’t). As ever, strive for a balanced diet, with sensible use of supplements if required, and you won’t be pushing at the boundaries of what may or may not be bad for you.

The more complex answer is this: You need to consider protein over-consumption on two levels.

1. The acute effect, i.e. short term or single dose. Here, what can happen with over-consumption is that the protein ends up being oxidised. Metabolically, this means that it is turned to glucose and/or fatty acids and contributes to your body’s fuel. Hence excess protein (contributing to excess fuel overall) is still potentially going to make you, or keep you, fatter if you’re in a calorie surplus. The deamination of the amino acids as part of this protein catabolism also means dealing with the amino groups (ammonium ions) NH₄ which may lead to point 2.  An excess amount of protein is likely to be around 0.5g/kg in one go, if in a meal, but if taking supplements, it is probably lower and more likely that anything over 0.3g/kg will be oxidised.
2. The chronic, or long-term effect. Here the effect of excess protein is a demand on processing the nitrogen (NH₄ ammonium) produced through protein deamination. This excess will need to be excreted via the kidneys by urea production. In addition, there may be alterations in acid-bases balance as a by-product, which may impact bone resorption, in order to buffer this shift in homeostasis (i.e. by liberating calcium from the bones). However, the evidence for this is not entirely clear. Protein consumption may actually be slightly protective to bones. There is no strong or consistent evidence on kidney damage or morbidity/mortality with high protein intakes.  But then again, it is difficult to longitudinally prove, as no one has performed longitudinal studies (over several years) where you can satisfactorily attribute effects directly to protein alone. Nor are there any studies looking at long term (years) protein supplementation.

The Lifebox Energy is designed to support activity and recovery for both men & women and therefore features various protein-packed vegan snacks such as Motion Nutrition organic roasted peanut vegan protein. If you are a gym bunny or have a protein enthusiast in your life, the Lifebox Energy is the ideal subscription gift for anyone searching for a protein-packed healthy snack.

¹ ‘Dietary protein and bone health: a systematic review and meta-analysis’ Darling et al, 2009