Superfood is a widely used catch-all phrase, common on the internet and in the marketing of exotic (and normally expensive) fruits and vegetables. Superfood is an over-used and over-hyped marketing tool, rather than a useful guide for consumers in choosing what foods to eat.

1. Superfoods or Supermyths?
Associate Professor Tim Crowe
School of Exercise and Nutrition Sciences
Deakin University
tim.crowe@deakin.edu.au
@CroweTim
www.thinkingnutrition.com.au
Nutrition @ DEAKIN
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2. What is a ‘Superfood’?
• Describes a food with a
high phytonutrient content
(antioxidants, fibre, selenium,
omega-3s etc.) that may
confer health benefits
• Has no meaning among nutrition scientists
• No legal definition of the term
• More an over-used marketing tool
• Most of the foods are fruits or vegetables
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3. Common ‘Superfoods’
• Blueberries
• Pomegranates
• Wheatgrass
• Goji
• Noni
• Mangosteen
• Açai
• Broccolli
• Garlic
• Pumpkin seeds
• Tea
• Soy
• Coconut oil
• Spirulina
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4. Goji Berry
• Lycium barbarum or wolfberry, widely grown in Asia,
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though most marketing focusses on Tibetan cultivars
Most research is in cellular and animal studies with
extrapolation made to humans
Claims relate to anti-cancer activity, aging, vision,
insulin resistance and infertility
Few clinical trials of any methodological quality in
humans – most only show improvements in antioxidant markers and subjective feelings
of ‘well-being’
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5. Goji
• Common claims they have the highest level of
vitamin C of all plants (claims up to 500-times an
orange!): completely false as has same vitamin C
content as an orange
• “18 amino acids”
• “Life extension” claims
• Can interfere with blood-clotting medications and
increase bleeding risk
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6. Acai
• Cherry-sized purple berry fruit of the acai palm
• Lab studies suggest it may have anti-cancer and anti•
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inflammatory effects, as well as a possible use in
treating heart disease
No human studies on its health effects yet published
“Six times the antioxidant level of blueberries“
“It is a poster child of the power of the Internet to
promote products for which only limited
phytochemical and pharmacological information is
available” Heinrich M et al. Phytochemistry Letters 2011;4:10-21
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7. Noni
• Lime-green Polynesian tropical fruit
• Noni fruit and juice derivatives have shown
anti-tumour activity in rats and mice, but few
clinical trials in humans
• Cancer patients given daily capsules containing
noni fruit extract (not juice)  no effect on
tumour regression, but ↑ QoL Issell BF et al. J Clin Oncology
2005;23 (June 1 Supplement):8217
• Some evidence for ↓ post-operative
nausea Prapaitrakool S et al. J Med Assoc Thai 2010;93:S204-9
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8. Wheatgrass
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Claims: Blood cleanser and ‘detoxifier’
attributed to the 'natural plant enzymes‘
and the chlorophyll content of the freshly-juiced grass
Common claim that 30 mL shot of wheatgrass juice is
nutritionally equivalent to a kilogram of vegetables is a
complete myth – has similar nutrient content to broccoli and
spinach
Floret of broccoli, or tablespoon of spinach, contain more
folic acid and vitamin C than 30 mL of wheatgrass juice
Chlorophyll is not absorbed by the body, requires sunlight for
activation, and its supposed high levels are no higher than
other green vegetables
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9. Antioxidants
• Found in foods (especially fruit and
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vegetables) that protect the body
from the harmful effects of free radicals
Free radical damage linked to development of cancer,
heart disease, Alzheimer’s and Parkinson’s, and is
linked to the aging process
Vitamins C, E and beta-carotene are the main
vitamins with antioxidant properties are
Other compounds also demonstrate antioxidant
properties e.g. selenium and lycopene
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10. Antioxidants
Total antioxidant capacity (TAC) measured using ORAC
(oxygen radical absorbance capacity) test
Wu et al. J Agric Food Chem. 2004;52:4026-4037
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11. An Apple a Day
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12. Cost-Benefit Analysis
• Five 30 mL serves of Noni Juice ($7.50) =
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1 navel
orange
Five 30 mL serves of Goji ($10) = 1 red delicious apple
Three serves of Acai ($2) = 1 red delicious apple
On a serve-by-serve basis, many common fruits such as
strawberries and apples, contain more antioxidants,
and are cheaper
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13. Why buy them?
• Superfruit juices contain a range of nutrients, but
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marketing spin vastly exaggerates their health benefits
Typically sold at high cost through multi-level marketing
Until better scientific evidence arises, cheaper and
wiser to get antioxidants from ‘traditional’ fruit and veg
sources
Since 1 July 2007, marketing of products as "superfoods" is
prohibited in the European Union unless accompanied by a
specific medical claim supported by credible scientific research
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14. Eat your Fruit and Veggies
• Hundreds of epidemiological studies linking F&V
consumption to ↓ risk of almost all major cancers
• Effect not from one particular food, but a wide variety
• ↑ F&V may decrease intake of more high-calorie foods
Mechanism?
• Antioxidants
• Fibre
• Polyphenols – antioxidant activity, inhibit cell
proliferation, phytoestrogenic activity
• Isothiocyanates (cruciferous vegetables) – increase
solubilising and inactivating enzymes
• Allium compounds (onions and garlic) – suppress DNA
synthesis, increase excretion
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15. Proposed Mechanism of Action of
Cruciferous Vegetables
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16. Top Foods to Consume
Literally thousands of natural chemicals in foods that
can affect our health
There is no one ‘superfood’
Think ‘super diets’ instead
Should not focus on the effect of a single nutrient, but
the total effect of food to health
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17. 10. Yoghurt
• Great source of calcium
• Low in fat and high quality protein
• Source of ‘good’ bacteria
• ‘Reduced-fat’ yoghurt may have more calories than
regular yoghurt – check the labels!
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18. 9. Lean Meat
• High-quality protein
• Great source of zinc, iron and
vitamin B12
• Choose lean cuts and grill or fry in a minimum
of oil and avoid charring
• Eat less than 500 grams (cooked weight per
week)
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19. 8. Dark Chocolate
• Dark chocolate has typically 2-3 times
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more cocoa as milk chocolate
Rich source of flavanols which are potent
antioxidants
Clinical trials show it can
– ↓ blood pressure,
– ↓oxidation of LDL-cholesterol
– ↑blood flow (by causing relaxation of the muscles lining
blood vessel walls)
– Improve the action of insulin
• Some evidence that regular eaters of cocoacontaining foods have lower rates of CVD
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20. 7. Tomatoes
• Contain a powerful antioxidant – lycopene
• Found in red/orange coloured fruit and veggies
• May offer protection against prostate cancer
• Cooking makes the lycopene more available to the
body (especially with a small amount of oil)
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21. 6. Soy
• High-quality protein
• Contains ‘isoflavones’ that have weak estrogen
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activity
Lower breast cancer risk and good for postmenopausal symptoms???
Soy found to lower LDL-cholesterol
Better evidence for soy than isoflavone supplements
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22. 5. Tea
• Rich in flavonoids (a class of polyphenols that have
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antioxidant activity)
May slow cancer growth and lower heart disease
Black and green tea both good, though greater
evidence for green tea for CVD
Some evidence of anti-depressant effects
Good source of ‘water’
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23. 4. Nuts and Seeds
• High in ‘good’ mono- and poly•
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unsaturated fat
High in vitamin E
Good source of fibre and protein
• Associated with favourable body weight outcomes
• Linked with CVD and diabetes protection
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24. 3. Oats
• Good source of protein and B-group
vitamins and low in fat
• Great source of fibre (important for keeping blood
sugar and cholesterol levels under control)
• Help with feelings of ‘fullness’ after a meal
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25. 2. Fish
• High in ‘omega-3’ fatty acids
• Good sources: salmon, herring, sardines and
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capsules
Edible bones for calcium
Offers protection against:
– Heart disease (stops blood from clotting,
improves heart beat rhythm, lower blood fats)
– Rheumatoid arthritis (anti-inflammatory)
– Mental health: depression, ADHD
– Dementia , Alzheimer’s
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26. 1. Cruciferous Vegetables
• Broccoli, cauliflower, turnips,
Brussels sprouts, bok choy,
cabbage, and radishes
• Broccoli: vitamins A, C, B group, and fibre
• Potent cancer protection: inactivate cancer-causing
molecules and act as antioxidants
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