🥩 Do high protein diets lead to kidneys damage?

There have been many news headlines saying how high protein diets lead to kidney damage.

This is mostly based on few older studies suggesting a correlation between higher protein intake and greater risk of chronic kidney disease (CKD). However, the majority of research could not confirm these results.

A recent analysis of 6 high-quality studies shed explored the correlation between different protein types (total protein, plant protein, animal protein) and risk of CKD.

Overall, greater intakes of protein were correlated with lower CKD. In detail:

• 16% lower risk for total protein

• 23% lower risk for plant protein

• 14% lower risk for animal protein, including fish

Increasing plant protein was associated with the greatest reduction in CKD risk, however this plateau at around 40g of plant protein per day.

The most common variables (e.g. geographical location, follow-up time, etc.) influenced this correlation.

🥊 Punchline

There is no evidence that higher protein intake does not lead to kidney damage, especially for plant based protein.

🫛 Muscle health: are plant protein any good for building muscle?

Intakes of plant protein has skyrocketed in recent years thanks to greater interest in gut health, adoption by fitness influencers and influence from other cultures.

Recent research on soy and wheat protein suggests that plant protein stimulate less muscle growth versus animal proteins.

This is likely because of the lower digestibility and uptake by muscles, leading to greater wastage of amino acids from plant protein.

The lower ratio of essential amino acids in plant protein, such as leucine, is a likely driver of this process.

However, very few studies have compared the effects of plant vs animal protein on muscle growth over time or examined a plant protein blend compared to just soy or wheat.

If wanting to maximise muscle growth through plant protein, there are some strategies:

• Consume plant protein with additional essential amino acids, mainly those in low quantities (methionine, lysine, leucine)

• Consume greater quantities of plant protein. If possible, given that excessive fibre intake may be detrimental to health

• Consume different sources of plant protein to provide a more balanced amino acid profile

Some research on Quorn protein has shown comparable results on muscle growth as animal protein. However, the majority of this research has been funded by companies making Quorn products and may be biased.

🥊 Punchline

Plant proteins are gaining popularity, but they are generally less effective at stimulating muscle growth compared to animal protein due to lower digestibility and essential amino acid content. However, strategies like supplementing with essential amino acids and diversifying protein sources can help mitigate these effects.

😋 Can protein drinks help with appetite control?

Plant protein are often deficient in certain essential amino acids and have lower rates of digestibility than animal proteins.

However, blending different plant proteins could compensate for these deficiencies, deliver greater amino acids to muscles compared to single plant protein and likely keep you fuller for longer.

A recent study compared the effect of whey, pea and pea+rice protein blend on amino acid concentration in the blood, appetite hormones and food intake.

• Amino acid concentration in the blood (often associated with greater muscle growth) was greatest with Whey protein intake. There was no difference between pea or pea+rice protein, despite complementary amino acids in the pea+rice blend.

• Appetite hormones and food intake after protein consumption was no different regardless of the protein drink. This suggests that the effect of protein consumption on appetite control is mediated by factors beyond amino acid concentration in the blood.

Whey protein delivers the highest amino acid concentration to the blood (and likely stimulate the greatest muscle growth), but this doesn’t translate to better appetite control.

🥊 Punchline

If you consume a protein drink to keep you going until the next meal, you could opt for a plant based protein drink rather than the standard whey protein.