About Dr. Sarah Brewer
After graduating from Cambridge University as a doctor in 1983, Dr Brewer was a full-time GP for five years and has worked in hospital medicine for almost 15 years. She is currently studying for a Masters degree in Nutritional Medicine at the University of Surrey, Guildford, and is a strong exponent of tree nuts as part of a healthy diet.
Dr Brewer is an award-winning medical writer, who is widely known in media circles for her credibility in promoting the taste and enjoyment of healthy foods. Her forthcoming series of books, under the Natural Health Guru brand, explores how good nutrition can help to overcome a number of common health problems such as arthritis, high blood pressure, asthma and diabetes. She firmly believes that, as well as tasting great, macadamia nuts offer an important contribution to a healthy diet. This is precisely why she has agreed to become the spokesperson for the Macadamia Advice Centre.
What’s so special about macadamia nuts?
"Macadamias are a very healthy snack choice as they contain a high percentage of good monounsaturated fats, which are also found in olive oil - one of the key ingredients of the Mediterranean diet. Traditional diets of Mediterranean countries such as Italy, Spain and Greece have been studied extensively due to the lower incidence of chronic diseases and higher life expectancy of people living there.
"Research now suggests that monounsaturated fat helps reduce the risk of heart disease and high blood pressure, by lowering harmful LDL cholesterol levels. Macadamia nuts also provide a natural source of plant sterols, which have been shown to be beneficial for cholesterol levels.
"Naturally low in sodium, they are also full of phytochemicals, vitamins, minerals, fibre and contain no cholesterol. Macadamias are also a good source of iron, calcium, selenium, Vitamin B and phosphorus.
Research conducted about tree nuts with similar composition is often applicable to macadamias, and other tree nuts have been proven to have significant health benefits. Recommended by the USA’s Food and Drug Administration, the Mediterranean Health Pyramid or diet recommends tree nuts, like macadamias, should be eaten daily."
Why are macadamias any different to any other nuts?
“Apart from its unique taste and crunch, there is one key reason to enjoy macadamias - they offer the highest levels of monosaturated fats of all nuts. The percentage of monounsaturated fats in macadamias is considerably higher than most other nuts popularly eaten in the UK including almonds, cashews, peanuts, pecans, pistachios and walnuts.“
Is there any scientific research into the benefits of macadamia nuts?
“Yes, with more being conducted all the time. Please see the health professional section for greater detail.“
Will they make me fat?
“Eaten in moderation as part of a balanced diet, macadamias will not contribute to weight gain. Research conducted in Japan showed that women’s body weight was actually reduced with a macadamia nut enriched diet, when compared with a higher saturated fat diet.
“‘Good’ fats are essential in a healthy diet. They make food tasty and give the feeling of being full, which stops people snacking unnecessarily. Providing macadamias are substituted and not in addition to other foods, there is evidence that they will either not contribute to weight gain or will reduce weight. USA studies of frequent tree nut eaters show that they usually weigh less than control patients.
“For instance, a dietary trial at Harvard University compared a low fat, low calorie diet with a low calorie diet containing ample fat from nuts and olive oil. Over 12 months both groups lost an average of 4.5 kgs with the diet containing nuts more successful in keeping weight off after a further 6 months and the participants showed no change in blood pressure. The summary concluded that healthy fats can be part of a weight loss program as long as total calories are controlled.”
Should I be concerned about food miles, if macadamias come from Australia, South Africa or America?
“Native to Australia’s Eastern coast, the macadamia tree will only grow in tropical climates with plenty of heat and rainfall. These conditions are necessary for the tree to bear nuts. They are not suitable for European climates as the rootball of the tree grows close to the surface of the earth, meaning that a frost is likely to kill the tree. Trade associations in Australia and South Africa are working hard with everyone involved to minimise the environmental impact all along the supply chain.”
What is your advice regarding nut allergies?
Immunoglobulin E (IgE) food allergies can be life-threatening, but thankfully are relatively rare. The nuts most likely to trigger allergic reactions are hazelnut, walnut, cashew and almonds. The nuts that are less frequently associated with food allergies are pecans, chestnuts, Brazil nuts, pine nuts, pistachios, coconuts and macadamia nuts. If you think you are allergic to certain nuts then it is important to avoid eating them. Talk to your doctor about being referred for nut allergy testing, and whether or not you need to carry an adrenaline pen and/or antihistamine with you at all times.
