Food: Protein

Everyone hears a lot about fats and carbs, but not so much about protein, the building blocks of the body. Dr Joe Kosterich talks about how much protein we need, sources of protein, protein supplements, the role of protein in exercise programs, and the advantages and disadvantages of high-protein diets.

Transcript

Nutrition and diet is something we hear a lot about and everybody hears a lot these days about fats and carbs; there are good fats, bad fats, good carbs and bad carbs. What we don’t hear so much about is protein and that’s what we’re going to be talking about today.

Protein is the building blocks of the body, whereas your fats and carbohydrates are the fuel that runs the body, the protein is the building blocks that actually make the body, so it’s a very important part of diet; but it’s something we don’t hear as much about. So where do we find sources of protein and how much do we need?

We’ll do the second one first because it’s a little bit easier albeit a little bit controversial and of course it’s going to depend on your circumstances. For most people, the recommendations for how much protein should you have is going to be about ten and thirty percent of your total calories per day. Now if you’re in training and especially doing any resistance type training, you may need some more protein because it is the protein that will be laid down in the muscle as it grows. Sometimes if people have been quite unwell and have lost some weight, they’re going to need some protein, again to rebuild that muscle that’s been lost.

Protein is also important for bones and of course it is found in your DNA, which is your genetic material, so protein is very important. It has been a little bit controversial as I said before as to how much one should have and people may remember the Atkins diet which was common in the seventies and never seems to go away, it recommended a high protein diet, like everything one shouldn’t have too much of a good thing. There’s a newer version around called the Eco-Atkins which has substituted a lot of animal protein with some vegetable protein and it’ll be interesting to see whether that gets popular over the next little while.

Two main sources of protein, there is animal and vegetable. The obvious source is meat, fish and chicken. Again with your meats, it’s important to have lean cuts of meat, chicken; aim sometimes for the skin off and fish obviously a good source of protein and also a good source of omega 3 fatty acids. How much protein should you have on your plate? Roughly a piece of meat the size of the palm of your hand and around the same thickness and you can apply the same idea to your fish or chicken.

For those who are vegetarian or vegan, there are protein sources that are non-animal based; these include things like legumes, lentils, chickpeas, red kidney beans, quinoa, which is a grain that’s fairly high in protein, and there are soy sources of protein as well, things like tofu. So even if you are a vegan or vegetarian you can still get your protein and it is important to do so. High protein diets have been popular with some people, like everything there are pluses and minuses, the advantage is that people do lose weight on them and that’s why they have remained popular, also people find they often don’t eat that much because a high protein diet will tend to leave you feeling fairly full after you haven’t eaten a lot of food. On the downside, people can get a little bit constipated on high protein diets and also sometimes people feel a little bit sluggish, the other downside is that sometimes people do get a little bit of bad breath on a high protein diet.

So rather than being high or low aim for the right amount, however if you eat your protein a little bit earlier in the day it has been shown that for example eggs for breakfast, people will lose more weight than if they’re having grains for breakfast so for those trying to lose weight, having your protein a bit earlier in the day, may be a good trick.

Now something that has become fairly popular in recent times are protein supplements, a lot of people for various reasons haven’t wanted to eat a lot of protein, especially those who don’t want to eat meat or animal based products and they sometimes sort of scratch their heads and say “well what else can I eat?” There are vegetable and vegan sources of protein such as lentils, chickpeas, kidney beans, soy, quinoa, but for a lot of people they say “look maybe it’s just easier if I take a supplement”. So these have become very popular and if you go into the health food stores, even the supermarkets you’ll find protein bars and protein shakes.

Like most things there probably is a role for them, certainly for people doing a lot of exercise, there is a strong case to me made for having some protein after you’ve done some exercise. In doing exercise, it does stress the muscles and that’s fine, that’s what it’s supposed to do, you then want to get muscle repair. Now because we know that protein is the building block of muscles, that’s a useful time to have some protein.

Some of your protein shakes are generally based on either whey which is dairy or cow based proteins or soy based proteins, these are the two main groups, now again those who are allergic to dairy or don’t want animal based products will tend to go for the soy based, other people may go for the whey based. Again it’s important to read the labels because some have a very high percentage of protein, as high as 98%, some have a lower percentage, it may be as low as 60% and the rest is carbs.

Those people wanting to lose or reduce weight you’ll want to have a higher percentage protein, for those who are not as concerned and might want a little bit of extra carbs because there doing perhaps distance running, then the ones with the lower percentage protein is quite ok and it might give you a little bit of energy which the higher percentage protein shakes won’t. As to whether you want to go with the soy or the whey based, that’s really personal preference.

Some of the shakes will also have various minerals in them, again that’s quite ok, it’s not going to be a daily requirement but it won’t do you any harm. Some of the protein bars, most of them have different flavours, they’re usually chocolate or coconut, something like that, they’re probably not quite as good as the shakes because they do have more sugar in them and again it is important to read the labels and sometimes they may have an assortment of additives or preservatives. So you just need to be a little bit selective to which one is best for you.

The other advantage of the shakes over the bars is that you have some water with it and that helps to rehydrate you, one advantage of the bars over the shakes is you can take it with you and you don’t need to find a tap and obviously have a container to fill it up, so again there’s a little bit of a role for both.

They should only be a supplement to your diet, you should not rely on any of these things as your main source of protein, but if used correctly as part of an exercise program and as part of a balanced diet, it may give you a little bit of extra protein and particularly for women they’re sometimes not getting enough so an occasional supplement with a protein shake is going to be quite ok for virtually everybody.

So once again like with most things of the body, you need to get the right amount of protein, as we said at the outset that’s going to vary a little bit according to your circumstances but roughly if you wanted to make a simple figure maybe twenty to twenty five percent of your calories coming from protein, depending if you’ve been unwell you might need a little bit more, if you’re doing specific training you might need a little bit more, don’t overdo it though.

More information

For more information on food groups and components, see Types and Composition of Food.

For more information on nutrition, including information on nutrition and people, conditions related to nutrition, and diets and recipes, as well as some useful videos and tools, see Nutrition.