5 Best Superfoods To Enhance A Healthy Diet

You might be surprised to learn that while it is widely used, the term “superfood” doesn’t have a legal definition. However, according to a recent Statista report, the global superfoods market was valued at $137 billion in 2018 and was projected to reach $204.6 billion by 2025. (27) Keep reading to learn more about what superfoods are and the best superfoods to incorporate into your diet for enhanced nutrition.

What are superfoods?

Although there is no official definition for superfood, it is typically considered as a food with high levels of nutrients or bioactive compounds that support human health, (29) such as:

• Fish (e.g., salmon)
• Fruits (e.g., berries)
• Legumes (e.g., lentils)
• Nuts and seeds (e.g., almonds, pumpkin seeds)
• Spices (e.g., garlic)
• Vegetables (e.g., dark leafy greens)

What are bioactive compounds?

Bioactive compounds are constituents, primarily found in fruits, vegetables, leaves, and grains in small amounts, that have the capability of modifying metabolic processes and affecting human health. (5)(16) The following list includes classifications of bioactive compound that may be found in certain superfoods:

• Alkaloids
• Capsaicinoids
• Carotenoids and tocopherols
• Glucosinolates
• Peptides
• Phytosterols
• Polysaccharides
• Polyphenols
• Polyunsaturated fatty acids (PUFAs)
• Terpenoids
• Triterpenes (5)

Bioactive compounds often have antioxidant effects. Antioxidants are compounds that counteract free radicals and help prevent oxidative stress, which when present in excess, can lead to cellular damage, disease, and low energy levels. (23)

Superfoods contain heightened levels of nutrients or bioactive compounds that support human health.

5 best superfoods to enhance a healthy diet

Although many foods can be considered superfoods (e.g., certain fruits, vegetables, legumes, fish, spices, nuts, and seeds), five superfoods that can be incorporated into everyday meals and support human health are described below.

1. Broccoli sprouts and microgreens

Broccoli sprouts and microgreens (seedlings) are produced from broccoli seeds and belong to the Brassicaceae family of plants. Broccoli sprouts include shoots and rootlets that emerge from germinated broccoli seeds and grow for two to seven days. Broccoli microgreens grow more fully than broccoli sprouts, emerging within seven to 21 days after they’ve been planted. (16)

The nutrient content of broccoli seedlings may have:

• Anti-inflammatory effects
• Anticarcinogenic effects (19)
• Insulin-modulating effects (2)

Broccoli seedlings contain 26 different compounds of glucosinolates (GLSs), secondary metabolites rich in sulfur that indirectly act as antioxidants in the body. Specifically, broccoli seedlings contain significantly higher concentrations of glucoraphanin, glucoiberin, glucoerucin, glucobrassicin, and neoglucobrassicin compared to a broccoli floret. (16)(22)(31) In the body, GLSs are hydrolyzed by enzymes to produce isothiocyanates (ITCs) such as sulforaphane (SFN), which are bioactive compounds that demonstrate anticarcinogenic effects. (16)

Broccoli sprouts and microgreens contain 37 different phenolic compounds, specifically flavonoid glycosides and hydroxycinnamic acids. Phenolic compounds are secondary metabolites produced in plants that possess antioxidant activity. (16)

Broccoli seedlings also contain several essential nutrients, including amino acids, fatty acids, dietary fiber, vitamins A, C, K, and folic acid, chlorophylls and carotenoids (pigments), and the minerals selenium, calcium, magnesium, and potassium. (16)

Broccoli microgreens and sprouts are rich sources of antioxidants. (16)

A study examined the effects of sulforaphane found in broccoli sprouts powder on insulin resistance in sixty-three patients with type 2 diabetes. The participants were randomly assigned to consume either 10 g of broccoli sprouts powder per day, 5 g of broccoli sprouts powder per day, or a placebo, for one month. After one month, serum insulin concentration decreased significantly by 44% in the 10 g group compared to the placebo group. This study suggests an association between consuming 10 g of sprouts powder and improved insulin resistance in individuals with type 2 diabetes. (2)

Isothiocyanates found in broccoli sprouts such as sulforaphane may also have anticarcinogenic effects. Sulforaphane may promote apoptosis (programmed cell death), reduce inflammation, alter susceptibility to different carcinogens, and reduce metastasis (spread of cancer). (19)(37)

2. Avocados

Avocados are considered a berry fruit. They belong to the Lauraceae family of plants and are native to Central America and Mexico. Avocados are unique because they contain a considerable amount of fat—about 25 g per avocado—compared to other fruits. Avocados can also be consumed as an oil. Compared to other vegetables or fruits, avocado oil is high in monounsaturated fatty acids (MUFA). MUFA oleic acid accounts for 45% of its total fatty acid content. (3)(17)

Did you know? In the United states, the consumption of avocados per capita increased from 2.2 pounds in 2000 to 7.8 pounds in 2019. (28)

Avocados contain many beneficial components, including:

• Bioactive compounds: B-carotene, tocopherol, and pyridoxine
• Minerals: potassium, phosphorus, magnesium, sodium, calcium, zinc, and iron
• Vitamins: ascorbic acid, retinol, thiamine, riboflavin, niacin, and folic acid (3)

Did you know? Avocados contain 60% more potassium than a banana that’s equal in serving size. (3)

As a result of its high nutrient content, avocados may positively affect cardiovascular, metabolic, and digestive function. (6)(30)(34)

A study examined the effects of consuming avocados on the gastrointestinal microbiota and microbial metabolites, as well as the fecal microbiota and fecal metabolites. Metabolites are the product of metabolism. After consuming avocado for 12 weeks, participants had an increased diversity of the intestinal microbiota, and increased concentrations of fecal fatty acids compared to the control group. These results suggest that avocado consumption may positively affect digestive physiology and improve gastrointestinal microbial diversity. (30)

A study examined the effect of avocado consumption on individuals following different diets meant to lower low density lipoprotein cholesterol (LDL-C), a type of cholesterol found in the body that in excess may build up in artery walls and lead to heart attack or stroke. A moderate-fat diet (MFD) with 34% fat that included one avocado per day reduced LDL-C, LDL particle number, small dense LDL cholesterol, and the ratio of LDL to HDL cholesterol. These results suggest that consuming one avocado a day as part of a cholesterol lowering, moderate fat diet, may have positive effects on certain cardio-metabolic risk factors. (34)

3. Blueberries

Blueberries are a blue fruit that belong to the Ericaceae family of plants and the genus Vaccinium, which also includes bilberries and cranberries. (21) Blueberries are known for their high levels of different antioxidant compounds including phenolic acids, ascorbic acid (vitamin C), and flavonoids such as anthocyanins (pigments that make ripe berries red, blue, or purple). Anthocyanins contribute to approximately 84% of the total antioxidant content of blueberries, and ascorbic acid contributes about 10%. (14)(26)

Blueberries contain anthocyanin, a powerful antioxidant compound that also provides blue, red, or purple pigment to certain berries. (14)

The antioxidant content of blueberries is influenced by growing practices, climate area, and how mature the plants are. Mature and ripe blueberries contain increased levels of anthocyanin by approximately 34% compared to less mature blueberries. During the ripening process, however, the content of other phenolic compounds may decrease as a result of anthocyanin increasing. (26)

The nutrient content of blueberries may positively affect:

• Cognitive performance (4)
• Type 2 diabetes (8)(18)
• Cardiovascular health (13)(25)(36)(38)
• Vision and eye health (35)

Post-menopausal women may develop hypertension and are at increased risk of cardiovascular disease as a result. A study examined the effects of blueberry on blood pressure and arterial stiffness in 48 postmenopausal women with stage one hypertension. After consuming 22 g of freeze-dried blueberry powder daily for eight weeks, systolic blood pressure, diastolic blood pressure, and brachial-ankle pulse wave velocity were significantly lower compared to baseline and the control group. Nitric oxide levels were also greater in the blueberry powder group compared to the control group.These results suggest that daily blueberry consumption may reduce arterial stiffness and blood pressure, perhaps in part a result of an increase in nitric oxide production. (13)

A small study examined whether consuming a supplementary blueberry concentrate rich in anthocyanin for 12 weeks enhanced brain function. Older adults were randomly assigned to consume either 30 mL of blueberry concentrate or a placebo. Participants performed cognitive function tests before and after the completion of the study. Magnetic resonance imaging (MRI) scanners were also used to measure brain activity throughout the study. After 12 weeks of consuming the blueberry concentrate, a significant increase in brain activity was observed in the blueberry group relative to the placebo group, and evidence of improvement in working memory was also observed in the blueberry group. These results suggest that supplementing with a blueberry concentrate may activate areas of the brain related to cognitive function and improve brain perfusion in older adults. (4)

4. Quinoa

Quinoa is a protein-rich, gluten-free seed that’s often considered a whole grain with several different varieties. Quinoa is part of the Chenopodiaceae family of plants and is native to the South American Andes region. (1) Quinoa seeds contain 11 to 19% protein, 49 to 68% carbohydrates, and 2 to 9.5% essential fatty acids. Quinoa also contains:

• Minerals: iron, calcium, magnesium, copper, and zinc
• Vitamins: riboflavin and folic acid
• Bioactive compounds: ferulic, sinapinic, gallic acids, rutin, isorhamnetin, and kaempferol (7)(32)(33)

Quinoa is unique because it contains all the essential amino acids that the body requires but cannot make on its own, making it a complete protein source. (9)

Did you know? Quinoa’s balanced amino acid composition is superior to soybean, barley, and wheat. (9)

The nutrient content of quinoa may positively affect:

• Cardiovascular health
• Cellular repair
• Immune function
• Metabolism of fatty acids (15)(24)

A meta-analysis that examined the effect of quinoa seed on cardiovascular disease (CVD) risk factors in adults determined that quinoa seed may be helpful as a supplementary option to more effectively control and prevent CVD in humans. Quinoa seed supplementation significantly lowered body weight and waist circumference, insulin serum levels, triglycerides, total cholesterol and low density lipoprotein levels. (15)

5. Sweet potatoes

Sweet potato is an edible root that belongs to the Convolvulaceae family and is a staple food in many Asian and African countries. Sweet potatoes can be purple, orange, white, or yellow. Orange fleshed sweet potatoes (OFSP) in particular contain considerably high amounts of antioxidant-rich carotenoids. (20)

Did you know? Carotenoids are bioactive compounds and natural pigments that contribute to the color of certain yellow, orange, and red colored foods. (20)

OFSPs contain approximately five carotenoids which include α‐ and β‐Carotene, β‐Cryptoxanthin, lutein, and zeaxanthin. Ascorbic acid, anthocyanins, phenolic acids and α‐Tocopherol are also found in OFSPs. (20)

Sweet potatoes contain 64% carbohydrates, which provide a great source of energy, as well as good amounts of soluble and insoluble fiber. OFSPs contain the minerals calcium, magnesium, phosphorus, potassium, iron, zinc, and sodium, as well as small amounts of protein and fat. (20)

The nutrient content of sweet potatoes may positively affect:

• Intestinal transit time
• Antioxidant levels

A study examined whether sweet potato could alleviate constipation in leukemia patients receiving their first chemotherapy treatment. Patients were split into two groups and received either routine nursing care, or routine care with the addition of 220 g of sweet potato per day. The sweet potato group experienced less constipation and more defecation satisfaction, suggesting a relationship between sweet potato intake and constipation frequency. (39)

Did you know? Consuming sweet potatoes may improve the vitamin A status of women and children with nutritional deficiencies. (10)(11)

An in vitro study that examined the antioxidant activity of purple sweet potato determined that both the inner layers and outer layers (which are often removed during processing) of the sweet potato contain considerable amounts of phenolic compounds, particularly anthocyanins. Anthocyanins are natural pigments that have protective effects in conditions such as cancer, inflammation, and CVD. (12)

The bottom line

Superfoods contain nutrients and bioactive compounds that may positively affect human health. Individuals can easily incorporate superfoods into their diet by consuming whole foods that are unprocessed, particularly plant foods such as vegetables and fruits. The body requires macronutrients and micronutrients in order to produce energy, and antioxidant rich foods may further support energy levels. Many foods can be considered superfoods and broccoli sprouts and microgreens, blueberries, avocados, sweet potatoes, and quinoa are some examples.