Pass the salt, please. We’ve all said it before — probably more than we think. While the recommended daily consumption of sodium is 2300mg, studies have shown that Americans consume well over that, with an average of about 3600mg per day — and especially those between the ages of 19 and 30 Reducing the population burden of cardiovascular disease by reducing sodium intake: a report of the Council on Science and Public Health. Dickinson, B.D. and Hava, S. Council on Science and Public Health, American Medical Association, Chicago, Illinois. Archives of Internal Medicine, 2007 Jul 23;167(14):1460-8. Sodium Intake Estimates for 2003–2006 and Description of Dietary Sources.. Institute of Medicine (US) Committee on Strategies to Reduce Sodium Intake; Henney, J.E., Taylor, C.L., et al. Strategies to Reduce Sodium Intake in the United States. Washington (DC): National Academies Press (US); 2010.. We’re actually consuming so much that the American Medical Association has openly suggested we reduce salt consumption all together Salt intake, blood pressure and clinical outcomes. Cook, N.R. Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts. Current Opinion in Nephrology and Hypertension, 2008 May;17(3):310-4.. So, we get it: Sodium can be bad for us. But it’s not all that bad — in fact, some amount is necessary for normal body function. So why should we care? Let’s take a closer look.
IT’S A SALTY, SALTY WORLD — THE-NEED-TO-KNOW
Around eighty percent of the sodium consumed by Americans comes from processed foods like cereals and baked goods (bet you didn’t know Cheerios and brownies are two salty culrpits) World Salt Awareness Week. He, F.J., Jenner K.H., Farrand C.E., et al. Journal of Clinical Hypertension (Greenwich). 2011 Mar;13(3):141-5.. The other eleven percent comes from shaking salt at the table or throwing in a few pinches to the frying pan while trying to imitate the latest Top Chef stars Salt intakes around the world: implications for public health. Brown, I.J., Tzoulaki, I., Candeias, V., et al. Department of Epidemiology and Public Health, Faculty of Medicine, Imperial College London, UK. International Journal of Epidemiology, 2009 Jun;38(3):791-813. Strategies to Reduce Dietary Sodium Intake. Cobb, L.K., Appel, L.J., and Anderson, C.A. Welch Center for Prevention, Epidemiology and Clinical Research, Baltimore, Maryland. Current Treatment Options in Cardiovascular Medicine, 2012 May.. But it’s not just what we add ourselves that can be a problem — processed foods are often high in salt, since it’s used as a preservative to keep food fresh longer.
So what is salt, exactly? Sodium is an element in table salt that is both necessary for certain body functions (more on that below), but that can also contribute to health issues like high blood pressure and heart disease when consumed in excess Determination of salt content in hot takeaway meals in the United Kingdom. Jaworowska, A., Blackham, T., Stevenson, L. et al. Faculty of Education, Community and Leisure, Centre for Tourism, Events & Food Studies, Liverpool John Moores University, I.M. Marsh Campus, Barkhill Road, L17 6BD Liverpool, United Kingdom. Appetite, 2012 Jul 4. Salt and high blood pressure. Mohan, S. and Campbell, N.R. Departments of Medicine and Community Health Sciences, University of Calgary, Calgary, Alberta, Canada. Clinical Science (London). 2009 Jun 2;117(1):1-11. Policy options to reduce population salt intake. Cappuccio, F.P., Capewell, S., Lincoln, P., et al. University of Warwick, Warwick Medical School, WHO Collaborating Centre for Nutrition, Coventry CV2 2DX, UK. British Medical Journal, 2011 Aug 11;343:d4995..
So why not just cut out salt completely? For one thing, some salt is essential. Important vitamins and minerals containing salt like iodine and sodium chloride can help maintain fluid balance, body temperature, and nerve and muscle function A hot topic: Temperature sensitive sodium channelopathies. Egri, C. and Ruben, P.C. Department of Biomedical Physiology and Kinesiology; Simon Fraser University; Burnaby, BC Canada. Channels (Austin). 2012 Mar 1;6(2):75-85. Hydration, sweat and thermoregulatory responses to professional football training in the heat. Duffield, R., McCall, A., Coutts, A.J., et al. School of Human Movement Studies, Charles Sturt University, Bathurst, Australia. Journal of Sports Sciences, 2012;30(10):957-65. The role of sodium channels in chronic pain. Levinson, S.R., Luo, S. and Henry, M.A. Department of Physiology and Biophysics, University of Colorado School of Medicine, Aurora, Colorado 80045, USA. Muscle Nerve. 2012 Aug;46(2):155-65.. Salt is also necessary to maintain proper blood pH (or balance between acidity and basicity). And for the athletes among us, salt is essential in maintaining healthy blood pressure, so athletes should be wary of sodium deficiency from overhydrating before competitions Hydration, sweat and thermoregulatory responses to professional football training in the heat. Duffield, R., McCall, A., Coutts, A.J., et al. School of Human Movement Studies, Charles Sturt University, Bathurst, Australia. Journal of Sports Sciences, 2012;30(10):957-65. Development of hydration strategies to optimize performance for athletes in high-intensity sports and in sports with repeated intense efforts. Maughan, R.J. and Shirreffs, S.M. School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK. Scandinavian Journal of Medicine & Science in Sports, 2010 Oct;20 Suppl 2:59-69. Fluid and electrolyte needs for training, competition, and recovery. Shirreffs, S.M. and Sawka, M.N. School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK. Journal of Sports Sciences, 2011;29 Suppl 1:S39-46.. Cutting back on salt too much may even increase cholesterol and triglyceride levels, which can contribute to heart disease Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride. Graudal, N.A., Hubeck-Graudal, T., and Jurgens, G. Department of Rheumatology TA4242/Internal Medicine, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark. , 2011 Nov 9;(11):CD004022..
We know — it’s tricky! To break it down a bit further, here’s what three experts had to say.
Rumor Has It — What the Experts Have To Say
Kent Berridge, a professor of neuroscience and psychology at University of Michigan who researches the brain bases of emotion, motivation, and reward to determine what drives pleasure, liking, wanting, addiction, and the structure of natural behavior.
Jason Edmonds, a biomedical researcher who works in the pharmaceutical industry and studies bacterial resistance to antibiotics and biological mechanisms strengthening autoimmune disease pathology. Edmonds is also a competitive Olympic weightlifter and one of Greatist’s experts.
So let's start with a basic one: What does salt really do to the body, and why can it cause problems?
Jeffrey Mechanick: [Salt] is an essential nutrient — it’s a chemical the body needs in order to function. So why does it cause problems? As we enter into a very recent phenomena of [consuming more and more processed foods] which contain added salt solely [for taste], we’re now overeating salt, more than our body [can handle]. As a result of all the extra salt, [fluids in the body compensate and increase]. As a result, blood pressure increases. But in general, across the board we don’t handle these high salt loads well. [In terms of causing disease] if you just associate salt consumption particularly among different ethnicities you see a higher rate of high blood pressure. As a result of [this high blood pressure], which is a risk factor for cardiovascular disease, you see more cardiovascular disease and more [cardiac] mortality.
Jason Edmonds: Excessive salt intake is probably best known for [its correlation] with high blood pressure and [its related] problems [like cardiovascular disease]. One theory for how this happens is that the kidneys sense [excessive salt in the body], signaling [our hormones to pump out more water and fill up the empty space] and this consequently increases blood volume. Some subsets of the population are at greater risk of suffering the ill effects of excessive sodium (African Americans, and those with high blood pressure, diabetes, and kidney disease). It's also worth noting that the association between salt and blood pressure in healthy adults with normal blood pressure is a matter of some contention. Apparently some studies have failed to uncover the correlation between high dietary sodium and increased risk of hypertension, especially in normal, healthy adults that don't fall into a high-risk category.
So is salt a necessity for our diet? And why do we like it so much?
Kent Berridge: Salt is a required part of a healthy diet. If the body loses salt, strong biological mechanisms kick in that give us an intense craving for it. Our normal liking for mild saltiness, and our [physiological need and desire for intense amounts of salt when deprived], are both products of our evolution. In the past, salty food has represented an opportunity to stock up on salts for the body, so we like it. Sometimes our ancestors had to go for long periods without salt. That created emergency mechanisms that make finding and eating salt a higher priority in states of need. Salty pretzels are normally nice but seawater or a handful of salt is nasty. But in a “salt-need state,” all of them start to taste nicer (because the body needs them).
Jason Edmonds: Salt (sodium chloride) is essential for maintaining a normal
[chemical balance] in the body. This is important for maintaining proper hydration levels as well as for proper functioning of bodily systems. We tend to crave savory foods and typically enjoy the taste of salt. Like sugars, salts were probably not nearly as abundant or easy to find during much of our evolutionary history. For this reason, we probably evolved to enjoy and crave the taste of sugar, salts, fat, etc., because when they were present we needed to ensure we got out fill. We've retained this craving for savory, sweet, and fatty foods, but in our modern culture — especially within industrialized nations — foods rich in salt, sugars, and dietary fats are abundant and readily available. As a result, we still crave them as if we're in a feast or famine state and so we end up consuming in excess of what we need to maintain proper physiological balance and health.
What’s the best way to cut back intake?
Jeffrey Mechanick: The first recommendation is to [learn how to] read nutrition labels and be aware of the salt and sodium content in processed foods. Number two is [to familiarize yourself] with healthy eating [practices]. A diet that’s high in fresh fruits and vegetables would be lower in sodium. [Evidence has] demonstrated that this can help to decrease blood pressure and the risks associated with it.
Jason Edmonds: It's important to moderate salt intake mostly to reduce the chance of developing hypertension — which significantly increases the chance of developing cardiovascular disease (CVD). In addition, salt has also been correlated with other problems such as stomach cancer and exacerbating kidney disease. The best way to cut back on salt intake is to limit consumption of prepared or processed foods, which are usually very high in sodium, preservatives, and other assorted unhealthy ingredients. Also [try to] resist [reaching for] the salt shaker. Many of our meals already contain sodium-rich sauces, gravy, and seasonings, so shaking salt onto those mashed potatoes along with a ladle full of gravy unnecessarily increases the sodium content. Choosing one or the other, or eliminating both and seasoning with crushed black pepper [or other fresh or dried herbs] are healthier alternatives for those consuming high levels of sodium in their diets (particularly for those predisposed to — or already dealing with — hypertension).
With this said, the scientific literature on the benefits of reducing salt intake are mixed. There's evidence showing that reducing sodium can lead to a modest but clinically relevant decrease in blood pressure.
[Some research also suggests] that the risks from high salt intake are overblown and excessive reduction can also be harmful. Many of these studies conclude… that reducing salt only lowers blood pressure slightly to moderately, and the reductions aren't [significant enough] to change the risk of developing cardiovascular disease. Some of these studies also say that salt reduction won't reduce risk of hypertension or cardiovascular disease in people with normal blood pressure.
What are your thoughts on salt consumption research?
Jason Edmonds: My opinion is that the average (even healthy) person should reduce their consumption of processed foods [regardless of their salt consumption or risk of related diseases]. These foods contribute to a large fraction of many people's daily salt consumption, but also typically contain other unhealthy ingredients such as unhealthy saturated and trans fats, high sugar, and preservatives. By limiting these foods [such as butter and margarine], you'll also be limiting a whole host of other ingredients that, in excess, can increase the chances of developing hypertension, [cardiovascular disease], and other health problems.
To cut down on salt intake, pay attention to the brands you choose, which can vary greatly in sodium usage. Read nutrition labels and learn how to interpret sodium content (e.g. “unsalted” foods still contain natural sodium but are made without sodium). Avoid processed foods (cut back on those french fries and even cottage cheese), cook with less salt by trying different substitutes and ditch that salt shaker from the table A comprehensive review on salt and health and current experience of worldwide salt reduction programmes. He, F.J. and MacGregor, G.A. Blood Pressure Unit, Cardiac and Vascular Sciences, St George's, University of London, London, UK. Journal of Human Hypertension, 2009 Jun;23(6):363-84..
What are ways you cut down your salt consumption? Share in the comments below!