Dietitian Catherine Gallagher compares the health-hype surrounding superfoods against their nutritional reality.

Cathy G

Catherine Gallagher from Donegal, a UK Registered Dietitian, writes a nutritional blog called What food can be with Cathy G…. Here, she examines the supposed heath benefits of five popular superfoods.

Information on the internet related to food, diet, nutrition and health is often vast, misleading and inaccurate, and it remains a huge task for dietitians to challenge these misunderstandings and misconceptions.

Today the term ‘clean eating’ appears to be a popular new approach to eating, driven by social media. Rather like the term ‘superfood’ and ‘detox foods’, these ‘healthy’ trends have no official definition or root.

To most, it’s not eating anything processed or eating foods in its most natural state, to others it’s a plant-based/vegan diet, gluten free, dairy free, meat free, organic – the list goes on.

In January 2017 Dr Giles Yeo investigated the latest diet crazes that bombard social media. This was broadcasted on the BBC, with an attempt to educate the public that too often these diet crazes and superfoods have the potential to do us more harm than good.  

Much of the information provided by these pseudo-nutritionists, is questionable, riddled with inaccuracies and misinterpretations, based on bad science at best, or personal experience, or beliefs at worst. Yet their coverage is far reaching. Much of the language they use categorises foods into good and bad, directly or indirectly.

There have often been accusations that their regimented advice can be driving eating disorders, particularly – orthorexia. This is an unhealthy obsession with eating healthy food where they systematically avoid foods and drinks they consider to be harmful, leading to extreme dietary restrictions, social isolation, lack of variety and ironically ill health.

Time to come clean!

I have researched what the British Dietetic Association had to say in relation to some renowned superfoods including; blueberries, goji berries, green tea, chocolate and garlic.


Are a source of vitamin K, vitamin C, fibre and manganese.

There have been claims on social media to suggest that blueberries can help promote heart health and prevent cancer.

Overall the research on the health claims of blueberries is inconclusive, however blueberries are a fantastic choice to help us reach our 5+ a day targets for fruit and vegetables. They are also low in calories and high in vitamins and minerals. Try including them in your day by:

  • Adding them to your breakfast cereal/porridge
  • Have them as part of a packed lunch
  • Pop them in as an afternoon snack
  • Mix them with low fat yoghurt for a delicious dessert

Goji Berries

Are a source of vitamin A, vitamin B2, vitamin C, iron and selenium

These shrivelled red berries are alleged to boost the immune system, brain activity and protect against cancer and heart disease.

However, that sounds berry inaccurate! The evidence behind the health claims around goji berries is weak.

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.

Overall, these products tend to be expensive and therefore wouldn’t it make more sense to spend our money on a variety of fruit and vegetables than to buy one expensive product with no proven health benefits.


Green tea

Green tea has been used in traditional Chinese medicines for centuries to treat everything from headaches to depression.

Green tea is alleged to boost weight loss, reduce cholesterol, combat cardiovascular disease and prevent cancer and Alzheimer’s.

Personally, I feel the idea that one size fits all is simply ridiculous. So, is green tea the booster of life or a trendy hype? Despite my personal love for this product, I’m going with the latter.

At present, there is no evidence to link drinking green tea as a protective mechanism against any types of cancer.

Notably, green tea contains caffeine. Caffeine in small quantities, may have a role in speeding up the body’s metabolism. However, a well-conducted review from 2012 of 18 studies, involving 1,945 people found no significant effect of weight loss from drinking green tea.

Green tea can be enjoyed as part of a healthy balanced lifestyle but by no means will it help you drop a dress size.


I apologise in advance to all the chocolate lovers out there! Can chocolate stop stress? In a small study from 2009, 30 healthy people who were given 40g of dark chocolate a day for 14 days experienced a reduction in stress hormones.

However, this study which was funded by a major chocolate manufacturer, had several limitations, including its short study period and does not provide any evidence chocolate has any benefits or effect on stress levels.

Most of the studies around the health benefits of chocolate have focused on cocoa extracts and not chocolate itself. Importantly, the potential health benefits of some compounds in chocolate must be weighed against the fact that to make chocolate, cocoa is combined with sugar and fat.

This means chocolate is an energy dense food, which can lead to weight gain putting people at higher risk of various diseases.

Chocolate can be enjoyed occasionally as part of a healthy, balanced diet. It should not be eaten every day and should not substitute other important food groups in the diet.


Garlic contains vitamin C and B6, manganese and selenium.

Health claims allege that garlic can effective against high blood pressure, Cardiovascular disease, cholesterol, colds and some cancers.

Garlic is a delicious flavour, used widely in Mediterranean and Asian cooking. It can be particularly useful in cooking as it provides an alternative to salt in adding flavour to meals, along with lemon juice, chilli, herbs and spices. Eating less salt is important to avoid high blood pressure.

For most of us at some point, we became familiar with the adage that garlic cures the cold! However, garlic does not appear to stand strong when the evidence has been scrutinised.

Overall 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 decrease risk of cardiovascular disease.

However, current evidence does not support the use of garlic supplements to improve health.

The super-sensible approach to food

To conclude healthy eating is about making sensible and sustainable food choices. It does make sense to avoid excessive intakes of caffeine, alcohol and high-fat, high-sugar foods and eat some fresh foods, which a lot of the clean eating movement suggest.

If you want to maintain optimal health then the best approach is a balanced diet, with at least five portions of vegetables and fruit a day; small portions of wholegrain carbohydrates; lean meat, fish and alternatives like beans and pulses; and low-fat dairy products. Keep to sensible alcohol and caffeine limits too.

If you are looking to lose weight then consider reducing portion sizes, and don’t forget to be active every day.

The superfood ideology too often advocated on social media is a marketing myth rather than a nutritional reality. They sound like a great concept and it would be fabulous if super foods existed and really delivered all that they promised!

Unfortunately, many of the claims made by super food promoters are exaggerated, not based on robust science and their alleged health benefits are not proven. While they may encourage some positive habits like eating more fruit and vegetables, it’s best to enjoy a balanced, varied diet and active lifestyle to keep your mind and body healthy.  

Cathy G xox –  What food can be with Cathy G… 

All studies were researched using the Cochrane library and PubMed websites. For further information on superfoods look at the British Dietetics Association and the Irish Nutrition and Dietetic institute.