Are you a vegetarian interested in reducing the carbohydrate in your diet? Depending on what you’ve been eating before changing to a low-carb (or lower-carb) diet, you may have to pay more attention to getting enough protein, as some of the usual sources of protein for vegetarians, such as whole grains, come with a pretty high load of glucose (starch is basically long chains of glucose). If you eat eggs and/or dairy, getting enough protein isn’t difficult. Vegan folks will have to pay closer attention.
As most vegetarians know, it isn’t just the total amount of protein that is important, but the types of protein. Our bodies need a variety of amino acids (the building blocks of proteins) and most plant foods are low in one or more of them relative to what our bodies need. This is one of the reasons it’s important not to rely too heavily on any one plant-based protein source. In addition, proteins from some plant foods aren’t as easily digested or absorbed (this is usually referred to by such closely-related terms as biological value, net protein utilization, bioavailability, and others). This means that the amount of protein in the food may not be the amount your body is actually getting, so it’s good to have a bit of a cushion.
Eggs are an excellent source of protein, with a distribution of amino acids that is considered “ideal” for the human body. Additionally, eggs are abundant sources of many other nutritional elements, some of which are difficult to get (especially in an easily-absorbed form) from plant sources. These include vitamin B12, choline, vitamin A (retinol) vitamin D, and easily-absorbed forms of lutein and zeaxanthin. If you choose eggs from hens which eat a varied diet (preferably “pastured” hens), the nutrient content of the eggs will be higher. A large egg has 6 grams of protein and less than a gram of carbohydrate.
Dairy Foods (Milk, Yogurt, Cheeses, etc.)
Dairy foods like milk, yogurt, and cheeses provide a lot of protein, as well as calcium and riboflavin. It is important to check the label for both natural and added sugars in these foods and make sure they fit into your own low-carb diet plan. Protein in dairy foods:
- Milk, 1 cup – 8 grams
- Cottage cheese, ½ cup – 15 grams
- Yogurt, 1 cup – usually 8-12 grams, check label
- Soft cheeses (Mozzarella, Brie, Camembert) – 6 grams per oz
- Medium cheeses (Cheddar, Swiss) – 7 or 8 grams per oz
- Hard cheeses (Parmesan) – 10 grams per oz
Soy-Based Protein Foods
The star of plant-based proteins is the soybean. If you tolerate soy well (and please be sure you do before diving whole-hog into large amounts, particularly in soy-based processed foods), it can be a real help in getting enough protein without too much carbohydrate. Soybeans are high in fiber, protein, vitamin K, iron, magnesium, copper, manganese, and riboflavin, as well as a variety of phytonutrients, including genistein.
Whole Soy Beans
Whole soybeans are the least processed way of incorporating soybeans into your diet, retaining all of the fiber, vitamins, minerals, and phytonutrients. I especially like black soy beans, as I think they taste quite a lot better than the yellow ones, and can be used in place of other beans in almost any recipe. As an added bonus, the most readily-available brand is organic and comes in BPA-free cans. It is also non-GMO.
A cup of cooked soybeans contains approximately 29 grams of protein, 7 grams of net carbs, and 10 grams of fiber.
Edamame (fresh soybeans) are another choice for whole soybeans.
- More About Black Soy Beans with links to recipes and sources
Made by grinding soy beans with water, soy milk is a decent source of protein (although it varies from brand to brand), but make sure to get unsweetened soy milk, as lots of sugar is added to most brands.
Tofu is made by coagulating soy milk and pressing the water out. It has a mild flavor, and a texture that easily soaks up whatever flavors you add to it. The silken type comes in shelf-stable boxes and is good for blending into shakes, puddings, etc. The refrigerated type is firmer and good for stir-fries and other cooking. You can press out more water to obtain a firmer texture, and bake it to firm it up even more. The amount of protein and carbohydrate in tofu varies by firmness and the method by which it is made. One brand has 20 grams of protein and 2 grams net carb in a half-cup serving.
Tempeh is made from whole soy beans which are cooked, fermented, and pressed into a cake. It is denser than tofu, and doesn’t soak up flavors as tofu does. In looking for nutritional data on tempeh, frankly it’s all over the place, so you’ll need to check the type you purchase. One brand has 19 grams of protein and 12 grams of net carb (plus 5 grams fiber) per 100 grams.
Other Soy Products – Many other soy foods (e.g. some of the soy-based “hot dogs” on the market) are made from soy protein isolate and other similar ingredients which are subjected to a lot of processing. Read labels carefully. (I’m not saying don’t eat them, I’m just saying be aware that you could be eating a highly-processed food.)
A Note on Grain-Based Proteins
Probably the biggest change that vegetarians encounter with a low-carb diet is the need to reduce grains. They contain some protein, and the amino acids in them complement those in soy and other legumes to provide all the essential amino acids. Unfortunately, wheat and most other grains are mostly starch. However, the protein in grains (mainly wheat gluten) can be separated out and used in a few ways.
Note: Sensitivity to wheat and gluten are on the rise. Be sure this isn’t a problem for you before consuming large amounts of wheat gluten.
Seitan and Vital Wheat Gluten
Seitan is made from the gluten part of wheat, so it is very high in protein and low in carbohydrate. It is sometimes called “wheat meat” or “mock duck”. It is formed into loaves, cubes, etc. One brand has 21 grams of protein, 3 grams of net carbs and 1 gram fiber for a 1/3 cup serving.
Vital wheat gluten is a powder made from drying wheat gluten. You often find it in recipes for low-carb baked goods. I can’t really comment on its use since I am gluten intolerant and have not tried it.
Rice Protein Powder and Other Protein Powders
Unlike wheat, most other grains don’t have enough or the right kind of protein to make something like seitan. However, rice and hemp, as well as other plants like soy and pea can be used to make protein powders. They are all processed to some degree or other but can be useful supplements to the diet in some circumstances.
Nuts and Seeds
Nuts and Seeds can make a contribution to your nutrional needs, including some protein. Most nuts and seeds have about 8 grams of protein per quarter cup.