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  • Yuzo Endo, M.D., Ph.D.
  • Masahito Hitosugi, M.D., Ph.D.
  • John E. Lewis, Ph.D.
  • Dan Kenner, Ph.D., L.Ac.

Doctor’s Health Advice

Doctor’s Health Advice

The Importance of Enzymes

No.2

Sodium and Cardiovascular Risk

For decades doctors have told their patients to limit sodium intake to prevent or reduce high blood pressure. Fears over salt first appeared over a century ago. In 1904 French doctors reported that six of their subjects who had high blood pressure, which is considered a risk factor for heart disease, had high intakes of table salt. This fear of salt increased in the 1970s when Brookhaven National Laboratory’s (U.S.) Lewis Dahl claimed that he had “unequivocal” evidence that salt causes hypertension. He was able to induce high blood pressure in rats by feeding them the human equivalent of 500 grams of sodium a day. (Today the average American consumes 3.4 grams of sodium, or 8.5 grams of salt, a day.)

Scientific tools have become more precise since then, and the correlation between salt intake and poor health is dubious. Intersalt, a large study published in 1988, compared sodium intake with blood pressure in subjects from 52 international research centers and found no relationship between sodium intake and the prevalence of hypertension. In fact, the population that ate the most salt, about 14 grams a day, had a lower median blood pressure than the population that ate the least, about 7.2 grams a day.

In 2004 the Cochrane Collaboration, an international, independent, not-for-profit health care research organization funded in part by the U.S. Department of Health and Human Services, published a meta-analysis of 11 salt-reduction trials. Over the long-term, low-salt diets, compared to normal diets, decreased systolic blood pressure (the top number in the blood pressure ratio) in healthy people by 1.1 millimeters of mercury (mmHg) and diastolic blood pressure (the bottom number) by 0.6 mmHg. That is like going from 120/80 to 119/79. The review concluded that “intensive interventions, unsuited to primary care or population prevention programs, provide only minimal reductions in blood pressure during long-term trials.” A 2003 Cochrane review of 57 shorter-term trials also concluded that “there is little evidence for long-term benefit from reducing salt intake.”

A meta-analysis of seven studies involving a total of 6,250 subjects published in the American Journal of Hypertension found no convincing evidence that cutting salt intake reduces the risk for heart attacks, strokes or death in people with normal or high blood pressure. As the authors of one recent paper wrote, “The overall evidence in the first half of the 1900s suggests that a low-salt diet was not a reasonable strategy for treating hypertension.”

In 2011 European researchers publishing in the Journal of the American Medical Association reported that the less sodium that study subjects excreted in their urine, a reliable indicator of prior consumption, the greater their risk was of dying from heart disease. These findings call into question the common wisdom that excess salt is bad for you. But the evidence linking salt to heart disease has always been questionable.

The most recent study, The Framingham Offspring Study, led by researchers at the Boston University School of Medicine, followed 2,632 healthy men and women aged 30 to 64 years with normal blood pressure over a period of 16 years. The researchers compared the participants’ sodium intake with their blood pressure readings. Surprisingly the participants who consumed lower quantities of sodium daily had higher blood pressurethan those who consumed more. One of the authors of the study, Lynn Moore, D.Sc. said, “We saw no evidence that a diet lower in sodium had any long-term beneficial effects on blood pressure. Our findings add to growing evidence that current recommendations for sodium intake may be misguided.”

The study found no strong evidence that cutting salt intake reduces the risk for heart attacks, strokes or death in people with normal or high blood pressure. In May of 2011 European researchers publishing in the Journal of the American Medical Association reported that the lower the quantity of sodium that study subjects excreted in their urine, the greater their risk was of dying from heart disease. These findings call into question the common wisdom that excess salt is bad for you. Consuming sodium in the form of MSG (monosodium glutamate) can have adverse effects, however. Studies have shown that MSG can raise blood pressure. Other studies in Thailand and China have also linked it with metabolic disease, diabetes and obesity. It is advisable to get dietary sodium from traditional sources such as miso and soy sauce.

If you still have doubts or concerns about sodium intake, most people can use more potassium in their diets, ideally from lots of vegetables. Potassium, like sodium, is also an essential mineral for fluid and electrolyte balance in your body. Eating a diet rich in potassium may counteract the effects of sodium on blood pressure and it may also reduce the risk of developing kidney stones. The general recommendation is 4,700 mg of potassium per day.

The best way to avoid cardiovascular disease is to balance sodium and potassium by eating a diet with an abundance of vegetables. In addition, there are supplements that can prevent and treat cardiovascular disease, such as proteolytic enzymes like nattokinase and oils rich in omega-3 fatty acids from fish or krill.

For decades doctors have told their patients to limit sodium intake to prevent or reduce high blood pressure. Fears over salt first appeared over a century ago. In 1904 French doctors reported that six of their subjects who had high blood pressure, which is considered a risk factor for heart disease, had high intakes of table salt. This fear of salt increased in the 1970s when Brookhaven National Laboratory’s (U.S.) Lewis Dahl claimed that he had “unequivocal” evidence that salt causes hypertension. He was able to induce high blood pressure in rats by feeding them the human equivalent of 500 grams of sodium a day. (Today the average American consumes 3.4 grams of sodium, or 8.5 grams of salt, a day.)

Scientific tools have become more precise since then, and the correlation between salt intake and poor health is dubious. Intersalt, a large study published in 1988, compared sodium intake with blood pressure in subjects from 52 international research centers and found no relationship between sodium intake and the prevalence of hypertension. In fact, the population that ate the most salt, about 14 grams a day, had a lower median blood pressure than the population that ate the least, about 7.2 grams a day.

In 2004 the Cochrane Collaboration, an international, independent, not-for-profit health care research organization funded in part by the U.S. Department of Health and Human Services, published a meta-analysis of 11 salt-reduction trials. Over the long-term, low-salt diets, compared to normal diets, decreased systolic blood pressure (the top number in the blood pressure ratio) in healthy people by 1.1 millimeters of mercury (mmHg) and diastolic blood pressure (the bottom number) by 0.6 mmHg. That is like going from 120/80 to 119/79. The review concluded that “intensive interventions, unsuited to primary care or population prevention programs, provide only minimal reductions in blood pressure during long-term trials.” A 2003 Cochrane review of 57 shorter-term trials also concluded that “there is little evidence for long-term benefit from reducing salt intake.”

A meta-analysis of seven studies involving a total of 6,250 subjects published in the American Journal of Hypertension found no convincing evidence that cutting salt intake reduces the risk for heart attacks, strokes or death in people with normal or high blood pressure. As the authors of one recent paper wrote, “The overall evidence in the first half of the 1900s suggests that a low-salt diet was not a reasonable strategy for treating hypertension.”

In 2011 European researchers publishing in the Journal of the American Medical Association reported that the less sodium that study subjects excreted in their urine, a reliable indicator of prior consumption, the greater their risk was of dying from heart disease. These findings call into question the common wisdom that excess salt is bad for you. But the evidence linking salt to heart disease has always been questionable.

The most recent study, The Framingham Offspring Study, led by researchers at the Boston University School of Medicine, followed 2,632 healthy men and women aged 30 to 64 years with normal blood pressure over a period of 16 years. The researchers compared the participants’ sodium intake with their blood pressure readings. Surprisingly the participants who consumed lower quantities of sodium daily had higher blood pressurethan those who consumed more. One of the authors of the study, Lynn Moore, D.Sc. said, “We saw no evidence that a diet lower in sodium had any long-term beneficial effects on blood pressure. Our findings add to growing evidence that current recommendations for sodium intake may be misguided.”

The study found no strong evidence that cutting salt intake reduces the risk for heart attacks, strokes or death in people with normal or high blood pressure. In May of 2011 European researchers publishing in the Journal of the American Medical Association reported that the lower the quantity of sodium that study subjects excreted in their urine, the greater their risk was of dying from heart disease. These findings call into question the common wisdom that excess salt is bad for you. Consuming sodium in the form of MSG (monosodium glutamate) can have adverse effects, however. Studies have shown that MSG can raise blood pressure. Other studies in Thailand and China have also linked it with metabolic disease, diabetes and obesity. It is advisable to get dietary sodium from traditional sources such as miso and soy sauce.

If you still have doubts or concerns about sodium intake, most people can use more potassium in their diets, ideally from lots of vegetables. Potassium, like sodium, is also an essential mineral for fluid and electrolyte balance in your body. Eating a diet rich in potassium may counteract the effects of sodium on blood pressure and it may also reduce the risk of developing kidney stones. The general recommendation is 4,700 mg of potassium per day.

The best way to avoid cardiovascular disease is to balance sodium and potassium by eating a diet with an abundance of vegetables. In addition, there are supplements that can prevent and treat cardiovascular disease, such as proteolytic enzymes like nattokinase and oils rich in omega-3 fatty acids from fish or krill.

Profile

Dan Kenner, Ph.D., L.Ac.

Dan Kenner, Ph.D., L.Ac.
Acupuncture and Integrative Medical College (AIMC Berkeley)

DAN KENNER, Ph.D., L.Ac graduated in 1979 from the Meiji College of Oriental Medicine in Japan, passed the Japanese National Licensing Examination and then trained in Internships at Osaka Medical University Pain Clinic and Kinki University Medical Teaching Hospital. He is licensed to practice Oriental Medicine both in the U.S. and in Japan. He also has a Ph.D. in Naturopathic Medical Science from the First National University of Naturopathic Medical Sciences. Dr. Kenner is on the Board of Directors of the Acupuncture and Integrative Medicine College in Berkeley, California and the National Health Federation. He is author of The Whole-Body Workbook for Cancer and other titles. Since 1983, he has endeavored to integrate the Naturopathic Medical Traditions of North America and Europe with the Traditional Medicine of East Asia.

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The Importance of Enzymes

・No.2 Sodium and Cardiovascular Risk

・No.1 Healing Enzymes