Please Pass the Salt
Please Pass The Salt
In the movie “Sleeper” by Woody Allen, the futuristic characters chuckle and say, “Remember when it was thought that cigarettes and fat were bad for you?” It certainly seems that ideas of health go back and forth like other trends. For instance, there is a growing body of evidence that a high carbohydrate diet, recommended by everyone from the American Heart Association to the strictest macrobiotic, may not be as healthy as we once thought (more on that in a later column). Now, some important studies have been done which emphasize the importance of that much- maligned substance, salt.
It is common practice to recommend a low salt diet (or more specifically, a low sodium diet, since we are talking here about sodium chloride, or table salt) in the general population, and particularly in hypertension. It is known that populations with lower salt intake have lower blood pressures generally. However, there is no good evidence that lowering a salt intake will lower blood pressure significantly, and certainly little evidence that it will modify the ill effects of high blood pressure, like heart attacks and strokes. Now comes a study from the medical journal Hypertension which shows that hypertensive people who lowered their salt intake most suffered the most heart attacks, almost four times the amount experienced by the group with the highest salt intake!
This result was not totally unsurprising. It is known that about half of hypertensives and a quarter of the population as a whole are “salt-sensitive“, that is, their system overreacts to salt by raising blood pressure. The rest of us don’t seem to react much to salt. However, in this “sensitive” population, increasing potassium, magnesium and calcium intake seems to control the sensitivity. So, taking adequate doses of these minerals (about 3500 mg potassium, 800-1000 mg for calcium, 1200-1500 mg calcium for post-menopausal women, and 500-800 mg magnesium) seem like a better idea, along with a moderate level of salt intake.
The kidney has a delicate mechanism (called the renin-angiotensin system) for maintaining pressure in the blood vessels. Artificially lowering one element of the system (sodium) causes an elevated renin level, and thus the kidney works harder to retain the salt that it has. In other words, the hypertension is a sign that a hormonal system is out of balance, and thinking we can starve it into submission may be naive. Sodium is necessary enough that a major adrenal steroid hormone, aldosterone, is devoted to its regulation and retention. Many studies show the necessity of dietary salt, from population studies showing a tendency toward shorter life span in people eating low-salt diets, to animal studies showing growth failure with sodium restriction. Multiple studies earlier this century showed fatigue and mental dulling to result from salt depletion diets.
Which brings me to the second exciting piece of medical information. Researchers at the Johns Hopkins University have published reports in Lancet and more recently, JAMA, suggesting that patients with Chronic Fatigue Syndrome can be helped by increasing salt in their bloodstream. More specifically, these patients (admittedly a small number so far) were found to have something called Neurally Mediated Postural Hypotension, which means that their blood pressure dropped down when they stood up, exercised, or with other activities that normally require the prompt reaction of the neurologic and adrenal systems to maintain blood pressure. When these patients were given higher amounts of sodium chloride and/or aldosterone (the adrenal hormone which keeps sodium in the body) they experienced less fatigue and brain fogginess (some patients were given other medications to increase blood pressure as well).
These studies are important for a number of reasons. Firstly, of course, is the possibility that this group of patients can finally be treated with a therapy that seems to have significantly positive effects. Chronic Fatigue Syndrome has only recently been accepted in the medical community as a diagnosis, and is still widely treated as a psychiatric disorder by physicians unaware of its prevalence and symptomatology.
Secondly is the support for the natural medicine concept of endocrine “exhaustion.” Much of the research on CFS has focused on hunting for “The Virus”, an infectious disease model more suitable to Pasteur and Ehrlich’s “Magic Bullets” and Jonas Salk’s search for a polio vaccine. However, many complementary medicine physicians, and other alternative providers, have treated CFS as a problem of coordination and depletion of the thyroid, adrenal, and other hormones, including neurotransmitters like seratonin. Thyroid support in the form of prescription or nutritional supplements like kelp and L-tyrosine have been helpful, as well as adrenal cortical extract, nutrients like vitamin C and pantothenic acid and herbs like ginseng and licorice which help the adrenal. Some physicians have given DHEA, an adrenal hormone (actually, the most prevalent hormone in the body) which is low in some CFS patients and is thought to relate to “reserves” of corticosteroid hormones. Some have suggest a topical preparation of wild yam, which contains natural forms of steroid hormones. Some have augmented the patient’s seratonin by using the newer SSRI drugs (mislabeled “anti-depressants”) like Prozac and Zoloft, [and herbs like St. John’s Wort and Valerian. ] Some patients have even been helped by low doses of natural hydrocortisone, to assist their body’s own production.
The researchers themselves are approaching their findings cautiously, assuming they are looking at a genetic predisposition to this condition which somehow becomes a problem. However, it is tempting to consider that they may be looking at one aspect of a hormonal “stress response” system (called the General Adaptation Syndrome by Dr. Hans Selye) and that supporting all the hormones naturally will coax the body back into balance.
Several broader issues are suggested by these studies supporting the use of salt. One is to reiterate that moderation is the best policy when discussing nutrition. As one wag put it, if you don’t like the evidence for a dietary recommendation, wait until the research supports what you do like. Up until the this century tomatoes were widely thought to be inedible, even deadly. Those of us who remember nutritional medicine pioneer Adele Davis exhorting us to eat brewer’s yeast must be glad that the fine lady is not around to see the bad rap yeast is getting in today’s nutritional circles. And one must wonder if Carrie Nation would have lived longer if she’d had that nightly schnapps that researchers now tell us will protect against heart disease!
Another is the importance of looking at individual differences, what Dr. Roger Williams called “Biochemical Individuality.” A portion of the population needs to lower their salt, the rest of us do not. About a third of the population is sugar and carbohydrate sensitive, others are less so. If we just lump everyone and look at Bell Curves, as our current medical studies do, we will miss the variations that make us all unique. This is the true value of many of the natural systems of medicine, that they approach everyone individually. Thus, it’s not unusual for a practitioner of Chinese Medicine to prescribe salt for a patient who is fatigued, especially if that person has darkish color in their face, a groaning voice, and a certain pulse quality. This signifies a weakness of the Kidney energy, which has to do with reserves, with the ability to sustain an effort physically or mentally. The taste associated with the Kidney is salty. Likewise, a complementary medicine provider might look for other signs of adrenal exhaustion, like dizziness, sugar cravings in the afternoon, and tightness of the mid back muscles over the adrenal gland. The art of seeing patients as individuals is being lost in the modern world of technological medicine.
The last issue is a reminder of how much a part of nature we really are. We came from the salty brine, we are bathed in salt in the womb, and filled with it throughout our lives. Wars have been fought over it, economies supported, and drab meals made tasty.