Virtually all plants contain protein, even fruit. For example, 5% of the calories in bananas come from protein, 8% of the calories in potatoes come from protein, 9% of the calories in brown rice come from protein, 36% of the calories in lentils come from protein and almost half the calories in green vegetables come from protein!
Examples of protein content within plant foods:
Black beans, boiled (1 cup)..15.2g
Broccoli (1 cup)………………..4.6g
Chickpeas, boiled (1 cup) ….14.5g
Lentils, boiled (1 cup)……….17.9g
Peanut butter (2 tbns)………. 8.0g
Quinoa, cooked (1 cup)……..11.0g
Spinach, boiled (1 cup)……….5.4g
Tempeh (1/2 cup)……………15.7g
Tofu, firm (1/2 cup)…….. ….19.9g
Leafy green vegetables, legumes, seeds and nuts are my favourite sources.
The only way to become protein deficient on a plant-based diet is to not consume enough calories from whole foods. For example, being a junk-food vegan, you will get plenty of calories, but they will be ’empty calories’ lacking nutrition. When you process a food and remove the fibre, you remove many other nutrients along with it. Not eating enough whole foods will make you malnourished in general.
Another example is where people eat whole foods, but they don’t get enough calories, such as though who choose a plant-based diet in order to lose weight. These people are getting protein and nutrients from whole-foods, but they aren’t eating enough calories, and this will cause them to become undernourished, not just in protein, but in general.
It isn’t necessary to combine different plant foods together in a single meal to ensure you are getting ‘complete proteins’. This is outdated science based on research into the protein needs of baby rats. The current advice is that you just need to eat a broad range of whole plant foods over the course of a day, and so long as you’re consuming enough calories, your protein levels will be fine.
Mind you, it does help if you place some emphasis on the word ‘broad’; for proteins, wholegrains, legumes, leafy green vegetables, nuts and seeds are particularly important. Each plant-food contains different protein building blocks, so by eating a broad range of foods, you can ensure you are getting all of them.