A nut is a simple dry fruit with one or two seeds in which the ovary wall becomes very hard (stony or woody) at maturity creating the shell. Any large, oily kernel found within a shell and used in food may be regarded as a nut. Examples include almonds, Brazil nuts, cashew nuts, chestnuts, hazelnuts, macadamias, pecans. pine nuts and pistachios and walnuts.
The term ‘nut’ is applied to many seeds that are not botanically true nuts. These may include cape seed, caraway, chia, flaxseed, linseed, passionfruit, poppy seed, pepita or pumpkin seed, sesame seed and sunflower seeds.
Chestnuts are more like a grain than a nut as they are low in fat and rich in low glycemic index carbohydrates and fibre. Peanuts are in fact legumes (like peas or beans), but are called nuts because they have many characteristics that are similar to tree nuts.
Coconuts are different again they can be a fruit, a nut and a seed depending on how they are botanical classified. Australian nut and seed consumption is increasing. Research has shown that regular nut consumption as part of a healthy diet can protect against heart disease and diabetes, and may help with weight management.
If eaten as part of a healthy diet in which total energy intake is controlled, nuts do not contribute to overweight or obesity.
Although seeds have not been as well researched as nuts their high fibre content is likely to contribute to satiety and appetite control.