Soy Protein - The good, the bad and the ugly
Have you ever checked the nutritional information in some meal replacement shakes and seen ‘Soy Isolate’ or ‘Soy Protein’ as their main ingredient and wondered if that was a good thing or a bad thing? Well, I'm here to bust some truths on soy protein isolate!
What is soy protein?
Soy protein powder is a highly processed form of soy used in cereals, protein bars, and snacks (among other foods). It's what remains when you take soybeans and strip all the sugars, fibre, and other natural vitamins and minerals from them, leaving only the protein.
Made through a process called acid-washing, soybeans get soaked in acid, water or alcohol to remove the sugar and dietary fibre. What's left from that gets dehydrated and turned into a powder.
Why Slim Mama doesn't use soy protein
Soy has had a bad rap since it contains soy isoflavones, which are organic compounds that can also be considered endocrine disruptors in high amounts. An endocrine disruptor (when absorbed in the body) can decrease or increase normal hormone levels, mimic the body's natural hormones, or alter the natural production of hormones.
The major concern is the endocrine disruptors called phytoestrogen in soy. Soybeans naturally contain phytoestrogens, which mimic the activity of estradiol, the primary female sex hormone (1). Historically, some people have been concerned that eating soy could increase levels of estrogen while decreasing testosterone levels. Although, phytoestrogens have been shown to have both estrogenic and antiestrogenic effects. This means that, while some phytoestrogens have estrogen-like effects and increase estrogen levels in your body, others block its effects and decrease estrogen levels.
According to Harvard Health Publishing (2), these effects of soy, as mentioned above, may have some benefits for both younger and older women, but also have some detriments.
Premenopausal women have much higher circulating levels of estradiol than postmenopausal women, and in this younger age group, soy may compete with the actual hormone for receptor sites in the body, thus decreasing the effect of excess estrogen. As too much estrogen can be linked with abdominal weight gain, fatigue and anxiety, this may be beneficial for premenopausal women. Many of these studies were however conducted by soy companies, so the consensus is still out on these study results.
The big concerning question for most women wondering whether soy is safe is - can it contribute or exacerbate breast cancer? Experts from the American Cancer Society (3) suggest that soy foods are healthy and safe (e.g. tofu). But soy supplements contain much higher isoflavone concentrations than food and aren't recommended until more research is carried out on them.
Another concern for women is the digestive effect it can have. If you have any digestive issues, a sensitive stomach, an inflammatory condition, or like to stay away from GMO's, you'd probably want to steer clear of soy protein powder as you could experience slight gastric distress from the soy protein. This is because soy can be hard to digest as soy protein has a higher concentration of trypsin inhibitors, which are chemicals that reduce available trypsin (an enzyme that helps digest protein in the body).
As for now, the consensus on soys effect on health isn’t black and white. There are some situations where it may be best to stay away from soy, but that generally differs from person to person.
Not all soy is created equal
Now we are just talking about soy protein powder here. There is growing evidence that eating traditional soy foods such as tofu, tempeh, edamame, miso, and soymilk may actually lower the risk of breast cancer. Soy foods are excellent sources of protein, especially when they replace other, less healthy foods such as saturated fats or processed meats. Soy foods have even been linked to lower rates of heart disease and may even help lower cholesterol. (3)
As for us at Slim Mama, the taste and texture (and the negative health effects it MAY have) was a major reason why we decided to steer clear from soy protein and use Whey and Collagen protein.
The main protein source found in the Slim Mama Shake is Whey Protein. Whey (pronounced WAY) is one of the two main proteins in milk (about 20%), the other being casein (about 80%). Whey is separated out during the manufacturing of cheese from dairy milk. It is then filtered, purified, and dried to form whey powder. Whey powder is low in lactose and contains all nine essential amino acids. This means it is a complete protein source, whilst retaining essential vitamins and minerals like calcium and vitamin B12.
Whey protein is among the most studied supplements in the world! It has a very high nutritional value, and scientific studies have revealed numerous health benefits. These include:
- Helps with weight loss
- Promotes muscle growth
- May lower blood pressure
- Helps keep you fuller for longer
- Improves immune function
- Helps control food cravings
- Helps preserve muscle when losing weight
As for the collagen in the Slim Mama Shake, collagen peptides are a versatile source of protein and an important element of healthy nutrition. Our bodies produce collagen, but like most things in the body it slows down with age. Other factors such as smoking, sun exposure, and an unhealthy diet can also reduce production.
So what's so good about collagen? Let’s see what the science says:
- Helps build muscle and burn fat
- May reverse ageing
- May help build strong hair, skin, and nails
- May reduce cellulite
- May improve digestive health
- May ease joint pain