Brazils nuts have soared 600 per cent in the last year, while walnuts are up 321 per cent, according to the UK's leading retailer Tesco.
The growth, also being seen in cashews (up 350 per cent) and almonds (up 90 per cent), is the first acute upturn in sales of all types of nut for decades.
Overall, demand for nuts of all types has increased 81 per cent since June 2004.
The popularity of the low glycaemic index (GI) diet could be fuelling the trend, said Damien Sutherland, nut buyer for Tesco.
"Most people associate nuts with Christmas and for years that was the main time that people bought them," he said. "Now, thanks to health experts talking up their beneficial qualities, they are extremely trendy and appear on many people's diet plans."
Nuts contain vitamin E, folic acid - which aids energy release from foods - and minerals such as zinc, which helps strengthen the immune system. A series of studies on almonds have shown that they can help lower cholesterol levels.
The £201 million nuts market grew by 11.6 per cent last year, as health-conscious shoppers bought 0.4 per cent fewer crisps and 4.4 per cent fewer crackers than in 2003, according to research analysts TNS. The firm also found that consumers are eight times more likely to eat nuts for health reasons than other bagged snacks.