Soy is arguably one of the most controversial nutritional topics.
Diets containing soy appear to be linked to health benefits, such as lower blood sugar, better heart health, fewer menopausal symptoms, and a lower risk of certain cancers.
Yet there are concerns about the healthiness of soy-rich diets. From a high risk of breast cancer, obstruction of thyroid function or feminizing effects in men, to name a few.

Soy is:
A nutrient-dense food.
Naturally rich in vegetable proteins.
It even contains all the essential amino acids that our body needs on a daily basis.
It can perfectly replace animal proteins during a meal or a 100% vegan diet.
It is also high in good vegetable fats, fibre, and several beneficial vitamins, minerals, and plant compounds.
Indeed, it is a natural source of polyphenols (an antioxidant) and more specifically isoflavones. These isoflavones are called phytoestrogens because of their ability to bind and activate estrogen receptors.
Due to their structural similarity, soy isoflavones are often thought to mimic the hormone estrogen. However, research suggests that soy isoflavones differ from estrogen in many ways, each having unique effects on the human body. These include:
lowering cholesterol, cardiovascular health, lowering blood pressure and blood sugar, improving fertility, reducing menopausal symptoms, improving bone health, and reducing breast cancer risk (ref.).
This being said, not all soy foods are the same in terms of their nutritional and health benefits.
Generally, the less processed soy foods are, the more nutrients they contain (amino acids, vitamins, antioxidant minerals). Conversely, the more processed they are, the more salt, sugar, fat and unnecessary and harmful additives they contain.
That's why it's important to focus on unprocessed soy foods, such as whole soy, tempeh, edamame, tofu, unsweetened soy milk and yoghurts.

Additionally, fermented soy foods, such as soy sauce, tempeh, miso, and natto, are significantly more beneficial for gut health but also reduce some of the anti-nutrients naturally found in fermented foods. of soy (Ref.).
The process of fermentation increases the nutritional value of food. It increases some vitamins and minerals and their capacity to be absorbed by our body (bioavailability). It also breaks down the antinutrients and predigests some of the nutrients, making them more digestible. Soy tempeh is high in calcium, iron, zinc, and vitamins from the B family like vitamins B9 and B12. It contains dietary fibre and prebiotics while has no cholesterol and is low in saturated fat and salt.
Tempeh can be enjoyed in many different ways, check some ideas below
Article written by nutritionist Aurelia Corbaz
References:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5088370/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3249631/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5188409/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5188409/