Genetic variants may explain why some people eat more salt than recommended, according to a study.
Preliminary research presented at the American Heart Association (AHA) in New Orleans has linked a specific gene variant that enhances an individual's bitter taste receptors with an increased use of salt.
'Genetic factors that influence taste aren't necessarily obvious to people, but they can impact heart health by influencing the foods they select,' said lead author Jennifer Smith, a PhD student at the University of Kentucky College of Nursing.
Previous research has shown two common variants of the TAS2R38 gene enhance sensitivity to bitter tastes, and can cause people to avoid heart healthy but naturally bitter foods, such as broccoli or other leafy greens.
The study analysed the dietary habits of 407 people in rural Kentucky who were taking part in a cardiovascular risk-reduction study. Researchers found that those who had one of the bitter-enhancing variants were 1.9 times as likely to consume levels of sodium above the AHA's recommended limit.
This increased consumption of salt is of concern because it is a risk factor for high blood pressure, which can lead to stroke or heart attack.
Smith said that evidence suggests 'that individuals who taste bitter more intensely may also taste salt more intensely and enjoy it more, leading to increased sodium intake'. Alternatively, she suggested that salt might be used to mask the enhanced bitter taste of some foods.
'By identifying which gene variant a person has, we may be able to help them make better food choices through education that is personally tailored to them,' Smith said. Over 90 percent of the US population has one of the two gene variants studied.
Dr Lawrence Appel, spokesman for the AHA, said the findings were interesting but described them as 'very preliminary' and said they needed replication.