Antioxidants are a compound found in foods that neutralise free radicals – harmful chemicals that generate widespread effects throughout the body, including chronic inflammation. The body is unable to generate antioxidants itself so they must be obtained in the form of vitamins in foods such as fresh fruit and vegetables. They also occur in other plant-based foods such as coffee, tea, wine, and chocolate.



By combatting the “oxidative stress” caused by free radicals, antioxidants help maintain healthier cardiovascular health, improved sugar processing, and several benefits to body-wide systems. Antioxidants may, therefore, help to lower the likelihood of cardiovascular disease, diabetes, end-stage kidney disease, cancer, and dementia.

Dietary fats are typically discussed in two forms: saturated and unsaturated fats.



Saturated fats are often found in dairy products, baked goods, processed foods, and fried foods. Saturated fats tend to be bad for health and it is generally recommended to limit their intake.



Unsaturated fats are more commonly associated with health benefits. These fats are commonly found in fish, vegetable oils, nuts, poultry, meat, egg, milk, and margarine spreads.



Cholesterol is also a form of fat, and the level of cholesterol in our blood stream is important to health (read more here). However, the amount of cholesterol in our food has only a small impact on our blood cholesterol levels. It appears more important to watch saturated fat intake than cholesterol intake.



Increasing publicity is being given to trans fats, which are common in processed foods, but research is limited in identifying its contributions to health. Trans fats are substances that were originally unsaturated fats but through processing have been modified so they now function similarly to saturated fats. Despite limited research being available, it is typically recommended to limit intake of trans fats. In regards to consumption of dietary fats, best health outcomes appear to result from substituting unsaturated fats in place of saturated and trans fats. Higher unsaturated fat intake is associated with lower risk of cardiovascular disease, type 2 diabetes, cancer, chronic kidney disease, and may help protect against dementia.



Interestingly, the overall intake of dietary cholesterol has relatively limited impact on health effects, possibly because it has little effect on the balance between HDL (“good”) cholesterol and LDL (“bad”) cholesterol in the body, which is a stronger predictor of health outcomes.

There are two broad groups of dietary fibres: soluble (which dissolve in water) and insoluble (which do not dissolve in water). Soluble fibres are often found in bran, flaxseeds, oat, cereal, and pears, and tend to delay the emptying of the stomach and slow digestion by forming a gel as they dissolve. Conversely, insoluble fibres are often found in brown rice, barley, cabbage, celery, and whole grains, and increase the efficiency with which the stomach processes foods.



Dietary fibres are believed to release chemicals giving people the feeling of “fullness”. This can lead to weight loss and better processing of sugars. They also help to improve immune functioning and offer a number of other health benefits. Even better, many high-fibre foods are also high in antioxidants, providing a combined benefit.



There is no level of fibre deemed “too much”. However, high consumption of insoluble fibres may lead to flatulence, bloating,and diarrhoea.

Sugar is a type of carbohydrate that comes in a number of different forms – you may hear sugars spoken about as fructose, glucose, lactose, and sucrose. Natural sugars are found in fruit, vegetables and dairy products, but can also be introduced to foods, most commonly in the form of sucrose from sugar cane, such as is added to many processed food and drinks.



Lower sugar intake tends to bring a number of benefits including lower body weight, risk of stroke, diabetes, chronic kidney disease, cancer, and dementia.



However, it is important to also consider the effects of “glycaemic index” to dietary sugars. Foods with a high glycaemic index have sugar content that is rapidly processed by the body, which means a larger, but shorter-lasting peak in blood sugar levels. Normally, a lower glycaemic index is preferred. Often soluble fibres help to delay the processing of food, which can contribute to a lower glycaemic index.

Whilst calcium is well known for its benefits regarding bone strength and density, too much may have adverse effects on the body so it is important to eat the right amount.



Calcium sources include dairy foods such as milk, cheese and yoghurts. Calcium-fortified products are also available, and these include soymilk, rice drinks and some breakfast cereals.



Both higher-and lower-than-recommended intake of calcium is associated with poorer health, including elevated risk of stroke, cardiovascular disease, diabetes, and some cancers.

Sodium plays an important role in many bodily systems. However, excessive consumption is harmful to general health and the general recommendation is that people should try to limit their sodium intake.



Foods high in added sodium include some breads and cereal products, cheeses, and many processed foods.



Foods low in sodium include fresh and unprocessed foods, such as fresh vegetables and fruit, frozen or tinned vegetables, fruit, and legumes (with no added salt), meats, fish, and milk.



Sodium has its strongest impact on the cardiovascular system, where reducing sodium intake tends to bring health benefits. However, it is important to note that the body does need some sodium intake in order to function well. Thus, both higher-than-average and extremely low levels of sodium intake are likely to have negative effects on health.