Salt intake directly linked to obesity: CASH

By Niamh Michail contact

- Last updated on GMT

“The food we eat is now the biggest cause of ill health through its high salt, fat and sugar content added by the food industry," said Professor Graham MacGregor, chairman of CASH and co-author of the study.
“The food we eat is now the biggest cause of ill health through its high salt, fat and sugar content added by the food industry," said Professor Graham MacGregor, chairman of CASH and co-author of the study.

Related tags: Salt intake, Nutrition, Obesity

There is a direct link between salt intake and obesity, says 1200-strong CASH study – but health experts say the findings should be taken with a pinch of salt.

The study, published in Hypertension Journal​, found that a 1 g increase in daily salt intake was associated with a 28% increased risk of becoming overweight or obese for children and a 26% increase for adults.

This was the first study to make a direct link between the two with consistent and significant results, wrote the authors.

Previous research had drawn similar but indirect associations between salt and obesity, suggesting that a high salt intake increased thirst and, consequently, raised consumption of sugar-sweetened beverages, while other scientists have placed blame with excessive consumption of processed foods that are high in calories and salt.

Mechanism unknown

Although the researchers did not yet fully understand the mechanism behind this, they suggested it may be because high salt consumption increased the volume of extracellular water, which led to increased weight. Another possible mechanism was that higher salt intake altered the body’s fat metabolism resulting in more fat deposits.

Victoria Taylor, senior dietitian at the British Heart Foundation, called for more research on the underlying mechanism but said the take-home message was to cut salt.

“Most of the salt we eat is already in the foods we buy, which is why checking nutritional information on packs to make sure we are making the healthiest choice is important to help limit the amount of salt we are eating,” ​she said.

Meanwhile campaigners said the findings had important implications for the food industry and public health.

Sonia Pombo, campaign manager at Consensus Action on Salt and Health (CASH), said: “The responsibility lies predominantly with the food industry, where most of our salt intake comes from, but people can also make a difference to their health by reading the labels and opting for foods lower in salt, saturated fat and sugars.”

Misleading?

But other health experts have said the study's conclusions should be taken with a pinch of salt.

Catherine Collins, dietitian at St George’s Hospital NHS Trust, said her interpretation was that a high calorie diet in general – in this case most likely from savoury foods due to the high salt intake – was predisposed to obesity.

"Obesity per se increases your risk of hypertension, which is made worse with higher salt food choices. [But] it’s impossible to select out one aspect of a whole diet to critique," ​she said.

Meanwhile Susan Jebb, professor of diet and population health at Oxford University, said the findings could be misinterpreted. "I would not want to see the public misled by the publicity around this paper into thinking that cutting salt alone will reduce their risk of obesity or help them to lose weight.”

But co-author and CASH chairman, Graham MacGregor, nonetheless said the findings demanded decisive action from government and industry to achieve a 30% reduction in population salt intake.

“The government and the food industry now need to take much stronger action. Unfortunately the previous government handed power back to the food industry with the Responsibility Deal which has completely failed to tackle these issues in the way that it needs to be,​he said.

The Conservative government’s Responsibility Deal was criticised for derailing a successful, nation-wide salt reduction programme at a purported cost of 6000 preventable deaths.

The study

Data was obtained from 458 children and 785 adults taking part in the UK National Diet and Nutrition Survey (NDNS), a cross-sectional study.

Researchers used data for weight, height, diet reporting and salt intake using 24-hour urinary sodium samples to calculate the increased obesity risk. They found that a 1-g/d increase in salt intake was associated with an increase in the risk of obesity by 28% in children and 26% in adults. Results were adjusted for age, sex, ethnic group, household income, physical activity, energy intake and diet misreporting.

Source: Hypertension

Published 2 September 2015, doi: 10.1161/HYPERTENSIONAHA.115.05948

‘High salt intake: independent risk factor for obesity?’  

Authors: Y. Ma, F. J. He, G. A. MacGregor

Related topics: Science, Prepared foods, Snacks, Reformulation

Related news

Show more

1 comment

The mechanism is well known, but it's ignored globally.

Posted by Zoltan Sandor,

Dear Victoria, Sonia, Catherine and authors of the paper in Hypertension!
The unnecessary sodium salts increase the incidence of every illnesses without any exception! We must feed ourselves according to maximum economy principle – but not the disorder – in our every cells. The maximum economy principle can be found in the composition of human milk, which is an evolutionary perfect food (from every viewpoint). Naturally, the composition of the human milk is the perfect guide for adult nutrition (sodium/potassium ratio, ratio between sum of alkaline metals and sum of polyvalent metals, ratio between metals and energy content, etc.).
The evidences: In the scientific literature & media the salt has political- & a lot of pseudoscience but real science of salt we can find only in traces because it’s really CENSORED globally. It’s time to understand, teach & use some very important but forgotten & ignored knowledge; fundamental natural laws/facts & to see the sad reality. The spontaneous diffusion of Na ions into the cells & the diffusion of K ions out of the cells continuously enhance the entropy (disorder). The task of the Na/K pumps to keep constant the intracellular concentration of Na & K ions. These cellular pumps continuously use energy (ATP). Excess Na intake = excess diffusion = excess increase of entropy = excess work for pumps = excess energy expenditure against excess entropy > excess food consumption. But all the rest of our vital processes (functional processes of the cells) receive less energy because our capacity (to make energy from foods) is limited. Everything work worse in our body & this increases the incidence of all illnesses without any exception, our aging & devolution accelerate etc. this is why Na-salts are perfect foods of entropy. 10th ed. of RDA was the best recommendation ever, 500 mg/day Na! Sugars & fats are foods & are sources of energy. But entropy & Na intakes = five decades global censorship, corruption, pseudoscience & lack of real science. Excess Na intake significantly enhances the entropy because the surface (billions) of cells is extreme large, this is the main risk factor of diabetes 1-2, overweight, NCDs etc. & our devolution is a considerable fact too. The law of entropy is the fiercest enemy of life & is our fiercest enemy too. NaCl isn’t food for humans but is perfect food of entropy. Every mmol excess Na & the wrong Na/K ratio & other wrong ratios increase more the entropy in our every cell, but the specialists talk about these rarely or NEVER. Excess Na intake doesn’t increase the oxidative pathway, but a critical surplus switches the anaerobic glycolysis on, in our every cell & we produce cytotoxic lactic acid. This is the Sodium-Induced Cellular Anaerobic Glycolysis. All of our vital processes & organs work worse (heart, brain, regulating systems, immune system etc.) & our cells are dying. We haven’t enough energy & enough time for the regeneration because we enhance the entropy in our every cell, day by day, again & again. The average lifetime of our cells shortens. Faster the telomeres run out. Our aging accelerates. We get sick often & we will die soon. Logical consequence: the unnecessary salt increases the incidence of all illnesses without any exception! This is the no named Sodium-Induced Disorder Syndrome. The entropy law finds our weak point or points & ravages mainly there, but increases the disorder in every cell in our body. We are no uniform, so other risk factors & circumstances affect the individual consequences. The growing entropy is our number one public enemy on every level; physical & mental health & social level globally. The evolution of life on Earth, our history & our entire individual life is a continuous war against entropy. But we, humans started our devolution = the entropy is growing in human genome. Even we nourish the entropy in our every cell (fundamentals of our existence) but the health scientists don’t talk & write about this. This is really a fatal error. Non-communicable knowledge is too much in salt science, it’s time to change that, because we will die out within 250 years!
“The Center for Science in the Public Interest in 1978 petitioned the Food and Drug Administration to revoke the generally recognized as safe status and limit salt, … It is unfortunate that government health authorities have not shown the will to act.” Source:
http://www.nature.com/ki/journal/v71/n1/full/5001951a.html
But the CSPI is weak, because they don’t use the already existing knowledge. This is awesome guilty irresponsibility &/or astonishing ignorance. Optimal ratios & quantities are in human milk. From every viewpoint the human milk is an evolutionary perfect food, including minimal energy expenditure of the Na/K pump & kidney of babies = possible minimum „entropy-transfer” into babies = healthy growing with maximal economy. So, the human milk is perfect guide to calculate optimal adult intakes. But the scientists ignore these facts. The health sciences made experimental animals from the humanity. The entropy is nourished in us with Na-salts, but they don’t talk & write about this. They are treating only the symptoms & consequences of the Sodium-Induced Disorder. Without real salt science – evidence based medicine & really preventive medicine doesn’t exist. Sodium recommendation is bad, education is astonishingly bad, the strategy against obesity, NCDs etc. is bad. True science of salt exists only in traces in the scientific literature, & in some articles even the traces are concealed & censored. In my article on science20 I collected the most important evidences (near 70 references) of the above ones:
http://www.science20.com/entropy_and_sodium_intakes_wicked_problems_health_sciences-120016
http://www.health.gov/dietaryguidelines/dga2015/comments/readCommentDetails.aspx?CID=3982
http://horizon-magazine.eu/article/science-common-language-commissioner-moedas_en.html#comment-1945038947
And read this, including my 2 comments:
http://www.science20.com/pfired_but_still_kicking/an_historical_moment_for_diabetes-156955

Report abuse

Follow us

Featured Events

View more

Products

View more

Webinars