Superfood is an unscientific marketing term used in various contexts. For example, it is sometimes used to describe food with high nutrient or phytochemical content that may confer health benefits, with few properties considered to be negative, such as being high in saturated fats or artificial ingredients, food additives, or contaminants. An often-cited example of a superfruit is blueberries which contain moderate-rich concentrations of anthocyanins, vitamin C, manganese, dietary fiber, pterostilbene (an undefined phytochemical under preliminary research), and low calorie content. Other examples of superfoods include broccoli, spinach, pumpkin, and tomatoes which are rich in various nutrients. All these fruits and vegetables contain a variety of nutrients and phytochemicals in varying amounts as do common plant foods like bananas, pineapples and potatoes which have only rarely been called superfoods. Fish may be considered a superfood due to their omega-3 fatty acids which may promote cognitive development.
The term is not in common use by dietitians and nutrition scientists, many of whom dispute the claims made that consuming particular foodstuffs have the health benefits often claimed by boosters of particular superfoods. There is no legal definition of the term and it has been alleged that this has led to it being misleadingly used as a marketing tool. The term superdrink is a variant term referring to beverages with the same supposed properties as superfoods, often used to refer to other categories of food, as in superfruits or supergrains.
The term is used frequently in a wide variety of contexts. It appears to first be referenced by Aaron Moss in the journal ‘Nature Nutrition’ in 1998, which stated, ‘Humans have many options when it comes to fueling their bodies, but the benefits of some options are so nutritious that they might be labeled as superfoods.’ In legal terms it has no standing however, although its use has been regulated in certain jurisdictions.
Possible health benefits and effects of foods described as superfoods are often disputed or unsupported by solid scientific studies. Superfoods may be represented by pseudo-scientific research, exaggeration or misrepresentation, while no peer-reviewed research has demonstrated their specific benefits.
Many recent superfood lists contain common food choices whose nutritional value has been long recognized. Examples of these would be berries, nuts and seeds in general; dark green vegetables (such as kale, collard greens, Swiss chard, Brussels sprouts, and broccoli); citrus fruits; fatty fish such as salmon, mackerel, and sardines; vegetables with bright, dark or intense colors (such as beets and their greens, and sweet potatoes); many legumes (peanuts, lentils, beans); and whole grains as a group. Possibly the most studied superfood group, berries, remain under scientific evaluation and are not proven to have any specific health benefits. Dark (ie, over 70% pure) chocolate may also be included in superfood lists, although its claimed merits remain unproven scientifically. Traditional fiber-rich foods like porridge and pea soup may be called superfoods. Others stress that it is as healthy to eat apples and oranges rather than expensive, exotic foodstuffs often cited without evidence as being superfoods.
The term superfood is often misused, with one expert saying it can be harmful when applied to foods which have drawbacks. For example, some seaweeds hailed as superfoods contain natural toxins which are thought by some to increase risk of cancer and liver damage.
Another consequence of the term superfood is that it is often used as a marketing strategy for companies. For example, green tea and its extracts have been studied over decades for their potential benefits, including possibly weight loss, as well as for polyphenol content that might supply other potential benefits. Many weight loss supplements contain green tea extracts as a key ingredient, due to a tea flavanol called epigallocatechin gallate (EGCG). However, there is no established scientific evidence that the consumption of green teas has any health benefits.