Soya Protein

Good Or Bad Choice?

By Xavier Fox

Bodybuilders are always looking for ways to get the proper nutrition they need while keeping their body fat levels in check. In addition, it becomes important to have variety in the diet, because dieting is tough enough without dealing with the monotony of eating the same thing on a continuous basis. The subject of using soya products often arises in many gym conversations, and like most supplemental forms of protein, there are arguments on both sides. Let’s take a closer look at soya to see if it should become part of our bodybuilding plans.

Most people are aware that soya is a source of protein, but there may be some that are not aware that it is actually comes from plants, more specifically, the legume family (things like beans and peas). A trait that legumes possess is that they are able to grab nitrogen from the atmosphere and transform it into nitrogen-based compounds within themselves. As you may already know, nitrogen is the element that makes protein significant. Soya is a legume that happens to contain high levels of protein, which accounts for 40% of the soya bean’s weight. Not only is it a legume that contains a lot of protein, unlike other vegetable products, the protein it contains has all of the essential amino acids it requires to become a complete protein so the body can fully assimilate it for muscle growth. That is why soya products such as tofu, soya flour, soya milk, and textured vegetable proteins have become popular.
Soya milk in particular has grown in use in the past several years. It is relatively high in protein at seven grams per cup, and it contains complex carbohydrates, good fats, and fibre. Thiamine, folate, calcium, phosphorus, potassium, iron, zinc, and phytochemicals are also plentiful in soya products. In addition, they contain oligosaccarides (raffinose and stachyose) that promote a healthy bacterial balance in the gastrointestinal tract. Of course, different brands will have different nutritional values, but there are many good choices out there. Be sure to review the labels when purchasing your soya products to ensure you get the ones that are lower in carbohydrates, because they will be lower on the glycemic index and the insulinemic index.
For instance, regular skim milk is low on the glycemic index, but it will cause insulin levels to spike. Soya milk, on the other hand, is low on the glycemic index and it does not cause insulin levels to spike. Since insulin will inhibit fat oxidation, it is important to keep insulin levels in check in order to maximize the amount of fat you burn. Another piece of good news is that studies have suggested soya protein intake is linked to increased fat oxidation, and it also keeps blood glucose and fat levels lower than whey and casein protein does.
Another impressive fact about soya milk is that it contains over 300mg of alpha linolenic acid (all soya products contain ALA), which is almost 15 times the 2% found in regular milk. ALA is one of the three types of omega-3 fats (eicosapentaenoic acid, EPA, and docosahexaenoic acid, DHA, are the other two). EPA and DHA are found in animal foods, but the only source for ALA is plant foods. Although ALA, DHA, and EPA are all omega-3 fats, they are not equivalent to one another. ALA is essential in our diet, and like the essential amino acids, we cannot manufacture ALA out of other substances inside our system… it must be ingested from outside sources. However, our systems can synthesize EPA and DHA from ALA. By consuming soya products on a regular basis, we can be sure to receive the many health benefits of ALA and the other omega-3 fats such as lower LDL cholesterol levels, lower risk of heart disease, lower blood triglyceride levels, improve immune system health, and reduce inflammation in the body.
Soya products also contain isoflavones, which possess many health benefits and act as powerful antioxidants as well. Recent studies show that isoflavones help women by easing the uncomfortable symptoms of menopause. As women enter this stage of life, their level of oestrogen reduces. Isoflavones can bind to the oestrogen receptor and lessen menopause symptoms as a result. For men, isoflavones have shown to inhibit prostate cancer growth, and they even caused prostate cancer cells to die. Isoflavones inhibit the growth of cells that form artery-clogging plaque, which can potentially lead to heart attack. For those of us that are getting older, studies have suggested that isoflavones help in the mechanisms that create new bone tissue. They may also play a role in the prevention of osteoporosis. Best of all, isoflavones have shown the ability to act in a similar manner as some cancer-fighting drugs, and they have demonstrated the ability to defend against tumours. And… the best source of isoflavones just happens to be soya beans.
The fact that soya beans contain isoflavones (phytoestrogens) has also been a source of controversy against the benefits of soya. This is because the chemical structure of isoflavones is very similar to that of our own oestrogen. That has led some to believe that soya could potentially interfere with the action of our own oestrogen as well as cause some of the negative side effects associated with oestrogen build-up in the system. Isoflavones can either inhibit or activate the activity of oestrogen; it depends on the type of oestrogen receptor within the cell (either alpha or beta receptors). Isoflavones can compete with oestrogen for the same alpha-receptor sites thereby decreasing the health risks of excess oestrogen. At the same time, when natural levels of oestrogen are lower than normal, isoflavones can help the estrogens by activating the beta-receptors.
The isoflavones in soya beans are genistein and daidzein. They are phytoestrogens, but will hardly create a physiological response in humans. As a matter-of-fact, when compared to synthetic forms of oestrogen, genistein has an activity level that is 1/100,000 as strong. Daidzein is only about 25% as strong as genistein. Therefore, in order to have an effect on your system, you would need to determine the amount of synthetic oestrogen it would take to affect you, and then consume enough soy to ingest 100,000 times that amount. I hope you’re hungry! Oh yeah… and just a side note… dairy milk contains estrone and oestradiol, which are real oestrogens.
Some of the paranoia was the result of a couple of studies performed by researchers named Dillingham and Gardner-Thorpe. Their studies were aimed at reducing the risk of prostate cancer with soy by modulating serum testosterone levels. Although they showed that prostate health was improved, there was no conclusive evidence that testosterone levels were lowered, especially to a point that it would create any negative effects or female characteristics. The effects on testosterone reduction were basically insignificant, and a later study (Maskarinec et al) showed that the reduced risk of prostate cancer from soya was strongly related to a non-hormonal mechanism. Therefore, the isoflavones in soya may reduce the risk of prostate cancer, but they will not reduce testosterone levels.
Another fault with some of these studies is that the subjects were made to eat diets that consisted of soya entirely, or the amounts of soya they were eating were abnormally high. Being that soya is rich in fibre, there is a possibility that the super-sized dosages of fibre created a lowering of testosterone, since diets that are very low in saturated fats and very high in fibre have been associated with lowering testosterone levels. The point is, these studies were done with models that hardly reproduced what would be happening in the real world. In addition, a recent study at the University of North Carolina determined that consuming soya would not cause adverse effects on the male anatomy even if consumed in extra-large amounts.
Other people trying to discourage the use of soya make the claim that since soya has a lower biological value than whey, it is not a good source of protein. Studies have shown that individuals involved in resistance training that were given whey and soya supplements gained the same amounts of muscle regardless of which one they used. The determining factor was simply using enough bioavailable protein… the source was not significant. Both whey and soya also exhibited antioxidant characteristics. As long as you eat enough soya, you should be able to gain just as much muscle as with any other protein source.
As far as adding protein to your diet, soya is more versatile than meat sources. Soya beans can be made into flour, so there is pretty much a limitless variety of foods that can be made from soya to enhance your protein intake. Try making “meat bread” for sandwiches or “meat muffins” for a snack. In addition, food made from soya instead of white flour would not have a high glycemic index, and it would not add fat to your body. There are many ways you can use soya to help you put on that extra mass.
Now, obviously you do not want to forsake all other sources of protein, and whey is still the best source out there, bar none. However, in order to provide some variety in your diet as well as to take advantage of all the other health benefits soya has to offer, it makes sense to include soya products in your daily food regimen. Low sodium, low fat, potassium, reduced cholesterol, stronger immunity, no insulin spikes, a healthier heart, lower risk of some cancers, versatility, and good amounts of protein all sound like sufficient reasons to head to the supermarket and pick up some soya products. And when you leave, you’ll probably notice that the soya was beneficial to your wallet as well.

Product	Serving Size	Protein (g)
Firm tofu	4oz (110g)	13
Soya sausage	1 unit	6
Soya burger	1 unit	10-12
Soya milk	8oz (225g)	6-10
Soya nuts	1/2 cup	19
Edamame	1/2 cup	12
Soya flour	1/2 cup	8-12