Raw Broccoli: Healthier Than Cooked?

Did you know that you can eat broccoli raw in salads and other dishes, and research suggests that raw broccoli may even be healthier than cooked broccoli – at least in some ways. According to a Dutch study published in the Journal of Agricultural and Food Chemistry, raw broccoli is a better source of sulforaphane than cooked broccoli.

For those who missed the memo, sulforaphane is a naturally occurring compound that may help prevent cancer through multiple mechanisms, including triggering self-destruction of cancerous cells, fighting inflammation, and modulating proteins that are involved in cell division (1).

This powerful compound is formed when a glucosinolate called glucoraphanin, which is abundant in some Brassica vegetables such as broccoli and kale, comes in contact with myrosinase, an enzyme that is released when broccoli or kale is crushed or chopped. It is also worth noting you will get plenty of sulforaphane regardless of whether you go for broccoli florets or stems because both release this powerful compound when chopped.

In the Dutch study, eight men ate 200 grams (about 7 ounces) of crushed broccoli, raw or cooked, as part of a warm meal. The researchers found higher levels of sulforaphane in the men's blood and urine when broccoli was eaten raw, suggesting that raw broccoli is more bioavailable than cooked broccoli (bioavailability of 37% versus 3.4%). What's more, sulforaphane was absorbed faster from raw broccoli than cooked broccoli, plus raw broccoli resulted in higher peak plasma amounts of sulforaphane than its cooked counterpart. (2)

In addition to being a better source of sulforaphane than cooked broccoli, raw broccoli contains much more vitamin C than broccoli that has been boiled. However, if you gently steam your broccoli rather than boil it, the loss of vitamin C will be minimal. (3) Other vitamins that are abundant in raw broccoli and that are usually easily destroyed by cooking, especially boiling, include vitamin B6, pantothenic acid and folate (4, 5).

Some of the best ways to eat broccoli in its raw state include eating bite-sized pieces of broccoli paired up with a healthy dipping sauce and eating finely chopped raw broccoli in slaws and other salads.

So, the bottom line is, eat your broccoli raw every now and then, provided that you don't suffer from hypothyroidism. Brassica vegetables like broccoli, kale and cabbage have goitrogenic properties, especially when consumed raw. Foods with goitrogenic properties act as thyroid antagonists, and people suffering from hypothyroidism or related health problems might therefore be better off avoiding foods like raw broccoli.

Furthermore, raw broccoli can cause digestive problems, so the key is to add it to your diet slowly, and only increase the amount if you notice your digestive system can handle it. What's more, as with all foods, eat raw broccoli only in moderation and as part of a healthy, balanced diet, and consult a qualified health care professional before making any drastic changes to your diet.

References

1. B. Mokhtari et al (2018). The role of Sulforaphane in cancer chemoprevention and health benefits: a mini-review. Journal of Cell Communication and Signaling, 12(1):91-101.
2. Vermeulen et al (2008). Bioavailability and kinetics of sulforaphane in humans after consumption of cooked versus raw broccoli. Journal of Agricultural and Food Chemistry, 56(22):10505-9.
3. F. Vallejo et al (2002). Glucosinolates and vitamin C content in edible parts of broccoli florets after domestic cooking. European Food Research and Technology, 215(4): 310-316
4. USDA National Nutrient Database for Standard Reference, Release 28
5. U.S. Department of Agriculture (2007). USDA Table of Nutrient Retention Factors, Release 6.