Kale is a superfood. And comedian Jim Gaffigan called for an end to “kale propaganda.” He believes kale is simply “real bitter spinach with hair.”
Okay, joking aside, what does science say about superfoods?
What is a Superfood?
Kris-Etherton, a Distinguished Professor of Nutrition at Pennsylvania State University, there are no superfood criteria. Nor is there a list of potential superffods.
A Woman’s Day article ran with a headline: 52 of the Healthiest Superfoods You Need in Your Diet. The odd thing about this headline is the seemingly large number of superfoods…at least 52, if this article is to be believed. Another thing of interest in the title is “healthiest superfoods,” which presupposes some superfoods are healthier than others.
So, our working definition for superfood comes from medicine.net: “Superfoods: A non-medical term popularized in the media to refer to foods that can have health-promoting properties such as reducing one’s risk of disease or improving any aspect of physical or emotional health. So-called superfoods may have an unusually high content of antioxidants, vitamins, or other nutrients.”
What Science Says About Superfoods
To determine the science behind superfoods, the National Health Service of the United Kingdom published a recent article. It is titled: Superfoods: The Evidence.
NHS teamed up with the British Dietetic Association to evaluate research on 10 popular superfoods, including: blueberries, goji berries, chocolate, oily fish, wheatgrass, pomegranate juice, green tea, broccoli, garlic, and beetroot.
Let’s examine blueberries and summarize the findings per Superfoods: The Evidence.
- A study in 2012 found 93,000 women who ate three or more portions of blueberries and strawberries a week had a 32 percent lower risk of a heart attack.
- However, the study could not prove the fruits caused the lower risk.
- While the evidence is inconclusive, blueberries may relax the walls of the blood vessels.
- This may help reduce the risk of atherosclerosis.
- Atherosclerosis can increase the risk of a heart attack and stroke.
- There is little evidence that blueberries protect against cancer.
- In animals, blueberry extracts may decrease free radical damage that can cause cancer.
- However, it is inconclusive if humans absorb these compounds from eating blueberries.
- Small animal studies found a link between blueberries and improved memory.
- However, these studies had small sample groups.
- There is no evidence linking blueberries and improved human memory.
Alison Hornby, a dietitian, reports: “While research on the health claims of blueberries is inconclusive, they are a fantastic choice as one of your five portions of fruit and vegetables a day.”
The Verdicts on the Remaining Nine Superfoods
The following verdicts are quotes from Alison Hornby.
- Goji berries: Various goji berry products are sold as health foods, but the evidence of their health benefits so far comes from scientific studies using purified extracts of the fruit at much higher concentrations than the products contain.
- Chocolate: A range of health benefits from the consumption of cocoa products have been investigated, particularly in relation to cardiovascular disease, with early results showing promise.” (Most studies concern themselves with cocoa, not chocolate.)
- Oily fish: The benefits of eating at least two portions of fish a week, including one of oily fish, include keeping your blood pressure at a healthy level and improving blood lipids, both of which reduce your risk of cardiovascular disease…
- Wheatgrass: There is no sound evidence to support the claim that wheatgrass is better than other fruits and vegetables in terms of nutrition. It cannot be recommended above any other choices in this food group.
- Pomegranate juice: Research suggests there may be a benefit, but we’ve not shown it yet. The studies that have found an improvement in existing health conditions were very small and more investigation into the role pomegranate plays in these improvements is needed.
- Green tea: In the Far East, green tea has been used as a treatment for a variety of conditions ranging from arthritis to weight loss, as well as a preventative measure for diseases such as cancer, although the evidence for the majority of these conditions is weak or lacking.
- Broccoli:…is a member of the family of cruciferous vegetables along with cauliflower, bok choy, and cabbage. These all contain compounds that are linked to improving the body’s ability to impede the growth of cancer cells.
- Garlic: Studies using high concentrations of garlic extracts have been associated with improved blood circulation, healthier cholesterol levels, and lower blood pressure, all of which reduce the risk of cardiovascular disease. However, current evidence does not support the use of garlic supplements to improve health.
- Beetroot: …and beetroot juice, along with green leafy vegetables, cabbage, and celery, are very useful as part of a balanced diet, as their nitrate content may help to reduce blood pressure.
How Super Are Superfoods
Would it disappoint you to learn that superfoods are not magic bullets? They do not cure all ills and lead to eternal youth. However, these food items are healthier ingredients to add to your diet. And you never know what verdict future science will reveal.
In the meantime, it seems that broccoli and oily fish have the greatest amount of positive science behind them.