Soy in skincare - Does soy cause cancer?
No! soy in skincare does not cause cancer. Here is why. Soy oil comes from soybeans, which come from a branching plant. Soybeans, like other foods, contain macronutrients such as carbohydrates, proteins, fats and fibre. When the fat alone is extracted from the soybean and gets refined further, it becomes soybean oil. In short, oil is 100% fat.
One gram of soybean oil contains one gram of fat and nothing else. A hundred grams of soybean oil contain a hundred grams of fat and nothing else. Oil is all fat.
Fatty acids are the building blocks of fat. Soybean oil contains 51% linoleic acid, a fatty acid that does a great job of keeping the skin well moisturized and improves its elasticity. We hand-picked soybean oil as one of the ingredients for Super Deodorant because it is readily available in Canada and USA. It is also reasonably priced, more stable than other plant based butters and stays on the skin longer.
Why does soy have a bad reputation?
The bad reputation is partly due to aggressive competitor marketing tactics and bro science.
Who could forget these famous sayings,
"An apple a day keeps the doctor away", advocated a savvy apple grower.
"Diamonds are a girl's best friend", said a De Beers campaign.
If you believe in these sayings, stay away from soy by all means. If you don't, keep reading.
Soybeans contain a weak plant estrogen called isoflavone. Isoflavones in high amounts are considered endocrine disruptors. Unbalanced hormone levels may increase the risk of cancer.
- 1 gram of soy protein from soybeans contain about 3mg of isoflavones.
100 grams of tofu contains 8 grams of protein.
100 grams of soy chunks contain 52 grams of protein.
100 grams of soy oil contain 0 grams of protein.
When 100 grams of tofu is consumed orally, the body gets 24mg of isoflavones.
When 100 grams of soy chunks are consumed orally, the body gets 156mg of isoflavones.
When 100 grams of soy oil is consumed orally, the body gets 0mg of isoflavones.
When a 70kg woman consumes 100 grams of soy chunks, her body will get 2.2mg of isoflavones per kilogram of her body weight. That's too low and it is not going to disrupt anything.
For hormonal disruption to happen in a 70kg woman, she must supply her body with 20mg of isoflavones per kilogram of body weight. That's 1400mg of isoflavones.
To get 1400mg of isoflavones from tofu, she must eat 2.8kg of tofu every day. 2.8kgs of tofu contains 4282Kcal.
To get 1400mg of isoflavones from soy chunks, she must eat 900g of soy chunks every day. 900g of soy chunks contain 3108Kcal.
It is impossible to eat so much soy in one day. Even if you do it for argument's sake, you will fight obesity before cancer.
Ethanol is a proven carcinogen yet many indulge in a glass of wine or a finger of whisky every day or frequently in a social setting. As food, enjoy soy in moderation as part of a balanced diet like everything else. When it comes to skincare, use it without fear. It is overall an excellent emollient.