Status: I spent about 30 minutes on this, and looked for authoritative mainstream sources. I would be excited to be proved substantially wrong, but it seems unlikely to me.

There are two factors here: how much do you need, and how much is in typical foods. I think most people have only a hazy idea of the first, and vastly underestimate the latter.

# How much protein do you need

• The RDA for protein is 0.8 g/kg of body weight. I weigh 56 kg, so according to that, I should have about 45 g of protein per day.
• That same link says people who exercise regularly should get 1.1 - 1.5 g/kg, so for me 61 - 84 grams.
• It again says those “training for a running or cycling event” need 1.2 - 1.7, so 67 - 95 grams.
• Menno Henselmans (who seems to be a respected source on body building and nutrition) cites a bunch of studies, and presents 1.8 g/kg as the absolute upper limit for elite body builders, beyond which no further performance increase is possible. 100 grams per day.
• That same article quotes some research showing endurance athlete performance (presumably far above my level) topping out around 1.3 g/kg. 72 grams per day.

So I need 50 - 100 grams of protein per day. As an active runner and cyclist, but not a lifter and very far from an elite body builder, I plausibly need somewhere in the middle of that range. More likely around 60 grams per day.

Takeaway: depending on your activity level, you can probably multiply your weight in kg by 1, and that’s how many grams of protein you need. If you’re very, very active, multiply it by 1.5. If you’re a lifter and trying to gain a lot of muscle mass, multiply it by 1.8.

# How much protein is in typical foods

I’m not vegetarian, but I am a little-tarian. I eat no beef or pork unless it’s about to be thrown away, and very little chicken or fish. Anyone on this side of the carnivore scale will be familiar with having to defend their ability to survive without the blessing of protein-packed animal flesh.

I downloaded an app called Calorie Counter. Given my vital stats, it said I need around 2150 calories per day, which seems about right.

I entered my meals from today^[1] , which was pretty typical:

• greek yoghurt (~4% protein) with muesli
• a banana and an apple
• some quiche
• some bean stew with feta
• bread, butter, jam
• a hot cross bun

This came to about 2100 calories. And… drumroll… 68 grams of protein! So on a day where I didn’t eat anything particularly interesting, and didn’t even eat quite enough calories, I still got enough protein to achieve maximum performance as an elite endurance athlete.

I tried entering a super boring day of food, 2150 calories worth of:

• greek yoghurt with muesli
• bread and vegetable soup
• baked potatoes with just oil (most of the calories here)

And it still came to 52 grams of protein. Comfortably over the RDA, though not quite up to the athlete-y numbers. In reality, I would sprinkle some cheese on the potatoes, have some peanut butter at some point in the day, etc. It only takes two slices of peanut butter on toast to get this day into elite athlete territory.

Takeaway: There’s protein all around us. If you eat a healthy diet that contains interesting (i.e. includes some amount of dairy, or dairy substitutes, or nuts or eggs or beans or…) vegetarian-ish food, or any amount of meaty food, you’re probably getting enough.

# Making it really simple

The key points are that you don’t need that much protein, and that most foods already have a lot. And because calorie requirements and protein requirements are basically functions of the same thing (age, weight, activity), we can combine these two observations into some simple numbers.

For my specific age (32) and activity level (active), I have the following:

• energy needed (calories) = weight x 38
• protein needed (grams) = weight x 1

From which it follows that my food should, on average, have 2.6 grams of protein per 100 calories.

If, instead, you’re 25, 180cm tall, weigh 75 kg, and are trying to become a pro body builder, your numbers above would be:

• energy needed: 43x
• protein needed: 1.8x

Resulting in a requirement of 4 grams protein per 100 calories.

So how much protein is in 100 calories of some typical foods?

• Potato: 3 g 
• Oats: 3.5 g
• Pasta: 3.8 g
• Milk: 5.4 g
• Eggs: 9 g
• Chicken: 11 g

Takeaway: in a very narrow sense, pasta is sufficiently proteiny for all but the gainiest of gains.

[1] ^{go back} Actually some day in March that I had recorded.