No need to consume more salt during hot months than in winter
Contrary to common opinion, there is no need for Israelis to consume more salt in the summer to compensate for much-increased sweating in the heat, according to research conducted by the University of Haifa. Health experts have often advised consuming more sodium during the summer months, but it is unnecessary, said Prof. Micha Leshem, a biopsychologist from the university’s psychology department.
The findings will come as good news for Health Ministry public officials, as they recently launched a campaign to reduce consumption of salt and to persuade food manufacturers to reduce the amount of sodium in their products. Too much salt in prepared foods raises the risk for hypertension, heart attacks and other illnesses.
Leshem and his team said previous studies found that populations who live in the desert consume more salt because they think they need to for a good balance of electrolytes in the blood due to perspiration from the heat. Salt is believed to leave the body through sweat in the heat, and there is a long-held assumption that drinking a lot of water during the hot months causes a deficit of salt.
The University of Haifa researchers said this policy is so accepted that in the US, for example, it is officially recommended to consume more salt in the summer. No study has been carried out to determine the effect of the seasons or climate on salt consumption, until now.
The study, published in the journal Appetite, includes results found by monitoring 140 students in Haifa, where the temperature is at least 10 degrees higher in the summer than in the winter. The participants were examined in both seasons and asked to avoid eating or drinking beverages except for water two hours before they were tested.
They were also examined according to the ways they consumed salt, such as how much they added to soup or how often they used the salt shaker and how many salty snacks they ate. Psychophysical tests were used to estimate their sense of saltiness. In addition, they were checked for their preference of sweets as a control to ensure that changes were not found to be general for the sense of taste, but instead distinctive for the salty taste.
The team found that neither the climate nor the seasons affect salt consumption, and water consumption is not different in the summer or winter. The preference for sweets, in fact, declined in the summer. “It may be that the same consumption of sodium in the winter and summer results from the minimum of exposure to hot temperatures because air conditioning is now so common in our environment,” Leshem suggested.