During the holiday season, you may have noticed yourself enjoying more meals and snacks than throughout the year. If the noshes have tasted particularly good, it's likely because of their high salt levels. Our salt intake throughout the festive season can end up far beyond what’s needed or recommended, which according to new research could be hurting your mood.
The physical toll salt takes on the body are well known. As salt levels rise, so does blood pressure, which can increase the risk of stroke or heart attack. Indeed, a July study found that adding extra salt to your food puts you at a higher risk of dying, regardless of the cause.
New research highlights the effects of salt beyond physical health. Too much can change behavior, specifically amplifying stress, according to findings published this month in Cardiovascular Research.
Salt consumption: Pros and cons
Not all salt is bad for you. Sodium is an essential element that contributed to the regulation of the movement of nutrients in and out of cells. The human body requires only a small amount of sodium, which combines with chloride to make up common table salt.
The American Heart Association advocates a daily limit of 1500 mg Na (3.75 g salt) for most individuals, particularly those with hypertension. Daily salt intake in the United States, and most other countries, usually exceeds this threshold. Researchers note that understanding how cells and organs respond to chronic high salt intake offers an additional route to improve health across an array of diseases, which led them to conduct the study on glucocorticoids (cortisol in humans, corticosterone in rodents), powerful hormones which underpin many important cardiovascular, cognitive, immune, and metabolic cell functions.
The research was performed over four years on adult male mice. It found that a high salt diet amplified glucocorticoid response to restraint stress.
The team fed the mice with either a control, low-sodium diet or a high-salt diet.
The researchers measured stress hormone levels in the morning and evening for up to 8 weeks. They took blood samples to assess the HPA axis response to stress.
Further, the scientists collected and analyzed tissue samples for genetic information about the hypothalamus, liver, kidney, and heart.
The study’s authors concluded that their research offers “functional evidence of a novel, direct connection between dietary salt intake and HPA axis activation.”
High salt intake led to high salt levels in the blood, a condition called hypernatremia, as well as fluid imbalance. Although the rodents had free access to water, they experienced an “activation of a water conservation response.”
Notably, because the study focused on rodents, there could be limitations for humans. Still, the researchers say it's a good idea to replace table salt with low-salt alternatives such as sodium chloride or potassium chloride.