Whey vs. Soy Protein


In order to have a fit and healthy body, it needs a regular supply of many vitamins and minerals and in order to get these, the body needs to consume a wide spectrum of food groups.

Protein in the body is important because it provides the building blocks (amino acids) for the cells to form. It helps to create new cells, rejuvenate old cells, and generally keep them in fully-working, fully-functioning order.

If you regularly exercise, your body will need more protein (and calcium also) in order to maintain good health. Exercise causes the muscles to contract and shrink and in doing so, can cause damage and tears. This is where protein comes in – it keeps the cells in the muscles, tendons, skin and organs in great condition, reducing the chances of these injuries occurring and also helping to heal them faster when they do.

Protein shakes have been very popular with athletes and bodybuilders for many years but they are increasing in popularity amongst people who want faster results from their diet and weight loss regimes. Two of the protein shakes that tend to be more popular are whey and soy protein shakes and the best of the two is often debated. They both have their advantages and disadvantages.

whey vs soy protein

Whey Protein 

One of the most popular protein shakes, whey protein has a longer-standing reputation amongst bodybuilders and athletes and for good reason. This is a fast-acting protein which means the benefits are pumped into the body sooner than other forms of protein. It is also considered to be a ‘complete’ protein because of the vast array of amino acids it brings to the table, all of which have been said to help with muscle gain, improved strength levels, and even a reduction in body fat.

Whey protein is also considered a high-quality form of protein, offering important essential amino acids such as Cysteine and Leucine.

Where does when protein come from? 

During the production and creation of cheese, whey is the liquid milk left over, containing two types of protein – whey (20%) and casein (80%). The protein is made when the whey compounds are isolated from this liquid.

What are the benefits?

As well as the benefits already mentioned – muscle gain, weight loss and increased strength, whey protein can also help to boost the immune system, provide nourishment to patients with diseases like cancer, improving memory and motor skills and even helping to improve and maintain the health of the cardio vascular system.

Where can you find whey protein?

Whey protein comes naturally in many foods and because it is a derivative of cheese and milk products, the common forms are dairy milk, ricotta cheese, yogurt, other cheeses and even goat’s milk.

Ricotta cheese contains the highest levels of whey protein at 28g per cup.

What are the disadvantages of whey protein? 

There are estrogenic chemicals present in whey protein which can lead to weight gain. Cattle farmers will use these chemicals to help their stock increase in weight.

Whey protein is also not suitable for those suffering with lactose intolerance and will cause a number of gastro-intestinal problems upon digestion such as bloating, gas and an upset stomach.

Whey proteins go through a pasteurization process before it is suitable for use which means many of the compounds can become damaged or unstable. This, in turn, would make them virtually useless on the body.

Soy Protein 

Soy protein is the first and only plant-based protein sourced categorized as ‘high-quality’ which, of course, has aroused interest in the athletic / bodybuilding / weight loss communities.

An extract of the super-healthy soybean plant, the protein extracted from it contains all of the amino acids in the correct and proper ratios to keep the body fit, healthy and working in the best capacity.

Studies have shown that soy protein, although coming with its fair share of disadvantages, can provide just as much (and in some cases more) effectiveness in the promotion of lean muscle mass. This makes it a relatively newcomer to the fitness world, but one that many people are quite rightly interested in.

Where does soy protein come from?

The soybean itself will be cleaned, cracked, conditioned and de-hulled before rolled into flakes at which point, the oil can be extracted. The flakes left behind are what can be used to create the soy protein.

You can find soy protein in three types:

  • Textured soy protein
  • Soy protein isolate
  • Soy protein concentrate

The soy protein isolate contains the highest level with almost 90% of the protein left as long when the flakes are dry. Texture soy protein usually comes in the form of imitation meat and will contain varying amounts.

What are the benefits? 

Because of the lack of lactose, soy protein is a perfect substitute for those unable to use whey protein. Not only that, those without lactose problems will also find soy protein, being a vegetable protein, is much kinder to the digestive system.

The proteins present in soy protein can have an interesting effect on the body’s metabolism, causing the thyroid to produce more hormone that regulates it. In turn, this can lead to weight loss as a side effect.

There are plenty of body-benefits aside from athletics plus points too. The extract of the soybean has been said to help with body circulation and heart health, lowering cholesterol. There have even been anti-carcinogenic links although these studies are currently ongoing.

Bone health is said to be increased when using soy protein over other protein forms. Animal proteins and other sources are said to decrease the amount of calcium in the body, and also its effectiveness, a negative side effect not present with this plant extract. Other high-protein sources have also been shown to have a heavy impact on the kidneys but once again, this problem doesn’t seem to be present with soy protein.

Where can you find soy protein? 

Meal-replacement drinks are often a high source of soy protein but you can also find it in meat-imitation products. Soy protein powders, the beans themselves, oil, soy milk and more can be bought formats health food stores.

What are the disadvantages of soy protein? 

You have the pasteurization problem again with soy protein, just as you did with whey protein. This means that many of the compounds may not even prove to be helpful in the body at all.

Although the problem of lactose intolerance seems to be fixed with this source of protein, it can still have a rather debilitating effect on the digestive tract and those with ‘sensitive’ stomachs may find that this form of harsh and tough fiber can be a little too much, causing upsets.

Soy protein can release phylates in the body which can inhibit the absorption of a number of vital minerals and vitamins and just one of these is iodine. This can have an impact on bone health, the function of various glands in the body (such as thyroid) and other health implications.

Whey vs. Soy Protein?

The protein of choice will depend on the way your body reacts to it and many athletes and bodybuilders will often find they need to choose between the two after trying them individually, or use a combination of the two together in varying ratios.

Whey protein isn’t good for those with lactose intolerance but soy protein can still cause an upset stomach, and the pasteurization process can have a negative effect on them both.

Whey protein vs. soy protein – it’s an answer that you will work out with trial and error.