If there's a question that plant based eaters soon get used to hearing, it's "where do you get your protein?"
The protein requirements laid out by the WHO are conservative overestimates, which means that a majority of wholefoods, most especially vegetables, nuts, seeds, whole grains and legumes will provide sufficient protein without the need for supplementation or powders or highly processed protein-enriched snacks. All wholefoods, even fruits, make a contribution to our protein needs, and the overwhelming majority of the other plant foods are actually complete proteins ie they contain all the essential amino acids required for humans. So why do we think they aren't? Why are we so often told that we must have beans with our rice, for example in order to make a meal which is adequate in protein?
There are probably two reasons for this; the first is simply a case of us being stuck in the past with old science. The first investigations into protein were carried out over 100 years ago on rats whose requirements for protein are more demanding than ours but as this wasn't known, we worked on the assumption that what was right for rats, was appropriate for humans, too. This knowledge was updated in the 1940s and ultimately incorporated into the current WHO recommendations, however like other long-established study results, the updated version doesn't always filter through very quickly to the rest of us.
But to return to the rice and beans example, whilst both are complete proteins, the suggestion that we combine them is probably very sensible, especially with respect to the rice - the majority of Britons eat white rice which, like any other refined grain can no longer be considered a complete protein. It is for this and many other reasons that we, Graham and Annette, focus 100% on wholefoods, anything else provides bulk but little meaningful nutrition.
Of course, it's worth adding that the information above is based on the assumption that we're eating adequate quantities of foods for our daily energy needs, determined by our size and level of activity. Most of us aren't challenged to eat enough, so we can do this, secure in the knowledge that plants most certainly do contain protein and a varied wholefoods diet, will provide adequate amounts rather than too little or, indeed, too much!