Goji berries (also known as wolfberries and red medlars) are the fruit of a plant, Lycium barbarum, that belongs to the same nightshade family as tomatoes and potatoes.
Goji berries grow naturally in China, Tibet and the Himalayas. They are also found growing in many UK gardens where it is sometimes referred to as the Duke of Argyll’s Tea Tree, as the leaves can be used to make a tea.
Goji berries nutritional benefits
Goji berries have an unusually high protein content for a fruit, at around 10%, which is similar to that of pecan nuts. When dried and eaten, goji berries provide around 414mg polyphenols per 100g weight making them an excellent source of antioxidants.
Goji berries are also an excellent source of vitamin C – even when dried, they provide around 45mg vitamin C per 100g.
Goji berries health benefits
Goji berries have been used in Chinese medicine or over 2500 years, to treat problems affecting the eyes, kidneys, liver and diabetes. Modern research is only recently starting to investigate these claims.
Goji berries and well-being: Results from four separate trials involving 161 people aged from 18 to 72 years showed that, compared with placebo, taking goji berry extracts was associated with significant improvements in weakness, stress, mental acuity, sleep quality, ease of waking, shortness of breath, ability to focus and overall feelings of health and well-being. Some showed additional improvements in fatigue, depression, circulation, and calmness, fatigue and dizziness. This suggests that Goji berries can improve physical and mental performance and overall feelings of health and well-being compared with placebo.
Goji berries and macular health: Goji berries are a rich source of antioxidant carotenoids, especially zeaxanthin, which is important for eye health and protecting against age-related macular degeneration. In a study involving 75 healthy older people, taking Goji berry extracts for 90 days had a stabilising effect on the retina, reducing loss of pigmentation and the ‘leakiness’ of retinal blood vessels, compared with placebo. Their blood levels of zeaxanthin also increased significantly.
Goji berries and type 2 diabetes: A study involving 67 people with type 2 diabetes assessed the effects of 300 mg goji powder extracts per day against placebo. After 3 months, there was a significant decrease in blood glucose levels compared with placebo, and the hypoglycaemic effect was most pronounced in those not taking any hypoglycaemic medicine. Circulating levels of ‘good’ HDL-cholesterol also increased.
Goji berries and inflammation: Obesity is associated with low-grade inflammation throughout the body. A clinical trial tested the antioxidative and anti-inflammatory effects of goji berries in 53 overweight people with raised cholesterol levels. After consuming 13.5g goji berries daily for eight weeks, significant reductions in oxidative stress and markers for inflammation were seen compared with placebo.
Goji berries and immunity: Goji berries are used in Chinese medicine to boost immunity. A study involving 150 healthy older people assessed the effects of goji berry extracts on immune responses to influenza vaccination. The 3-month trial found that taking goji berry extracts was associated with a significantly higher level of influenza-specific immunoglobulin G antibodies from 30 days after vaccination, compared with placebo.
Goji berries and weight loss: Goji berries are often marketed for weight loss. Two small, randomized, double-blind, placebo-controlled studies have found that Goji berries can increase metabolic rate and reduce the waist circumference compared to placebo. In a 14-day trial, involving 15 people, those taking Goji berries had a significant 5.5cm decrease in waist circumference compared with just 0.9cm reduction in those on placebo. Strangely, this has not been followed up!
Goji berries dose
A typical dose for goji berries in supplement form is 1g to 2g concentrated extracts daily.
For dried Goji berries, eat a handful or 10g to 30g daily.
Adding Goji berries to your diet
Goji berries are widely available in healthy bars, snacks, coated in chocolate and added to cereals and trail mix. They are particularly delicious and rich in polyphenols when coated in dark chocolate.
Here’s my recipe for Pecan Punch Trail Mix which teams goji berries with other nutritional powerhouses.
Pecan Punch Trail Mix
- 200g (2 cups) shelled pecan halves
- 100g (1 cup) cacao nibs
- 100g (1 cup) dried goji berries
- 100g (1 cup) hulled pumpkin seeds
- 1 teaspoon fresh ground cinnamon
Chop the pecans into smaller chunks if you wish – this is twice as quick using a double-bladed mezzaluna knife – but I like to use them whole.
Combine all ingredients in a bowl and mix well.
Image credit: philipp_alexander/flickr