Salt Institute cites new research in call to abandon government guidelines on salt consumption (Press Release)

FOR IMMEDIATE RELEASE                        Contact: Dick Hanneman    Phone:  703-549-4648

October 29, 2009                                                                                        dick@saltinstitute.org

Salt Institute cites new research in call to abandon government guidelines on salt consumption

Alexandria, VA (October 29)… The Salt Institute has renewed its call to abandon numeric targets for Americans' salt consumption.  In a letter to the Dietary Guidelines Advisory Committee, Salt Institute president Richard L. Hanneman pointed out recently published evidence that salt intakes are unchanged over decades and in a range above that recommended in the Dietary Guidelines for Americans.  This may represent, he said, not uneducated consumer behavior, but a physiological “salt appetite” resistant to either public education or re-engineering the U.S. food supply.

The body's consistent physiological salt appetite has the perverse result of increasing caloric intake instead of curtailing dietary sodium, he added.

The Institute called for further study and for replacing the numeric target in the 2005 Guidelines with a call for "moderation" as contained in Guidelines beginning in 1980 until 2000.

Text of the letter:

October 28, 2009

Linda V. Van Horn, PhD, RD, LD

Chair

and

Members

Dietary Guidelines Advisory Committee

Dear Committee members:

The Dietary Guidelines Advisory Committee (DGAC) will be conducting its fourth meeting on November 4-5.  We would like to supplement our earlier comments[i] by re-emphasizing our earlier endorsement of a need to focus on overall dietary quality and calling to your attention recent research on dietary salt intake that questions the fundamental strategy of the Guideline on salt, namely that inducing persons to substitute low-sodium foods into their diet will achieve the policy objective of reducing overall dietary sodium intake.

We reiterate our view that evidence of the health outcomes of diets reduced in sodium show no benefit in terms of reduced mortality[ii] and remind you that the single controlled trial of this hypothesis found that subjects in the salt-reduced group of the cohort had a considerably greater incidence of mortality and more frequent re-hospitalization.[iii]  These are crucial points, but suffice a short reminder at this point in your deliberations.

We have also presented evidence earlier concerning the health benefits of a quality diet which we believe should be the focus of your recommendations.  Specifically, we would further call your attention to the accumulating evidence – and consensus public perception – of the healthfulness of the Mediterranean Diet.  Attached is an analysis of those issues prepared by Salt Institute technical director Morton Satin.[iv]  Please note that the Mediterranean Diet contains significantly more salt than the American Diet.  Salt intakes in this normal range are fully compatible with human health.

Beyond these points that reducing Americans’ intake of salt will not improve health and that an overall improvement in diet quality is a proven, superior approach, a recent study in The Clinical Journal of the American Society of Nephrology indicates that physiology, not public policy, will determine a human’s daily sodium intake.

This research likely represents a important step forward in light of past Dietary Guidelines to reduce dietary salt and, since the 2000 Guidelines, to set progressively restrictive guidelines for salt intake among U.S. citizens.

The study, “Can Dietary Sodium Intake be Modified by Public Policy?”[v] analyzed existing research to determine whether sodium or salt intake follows a pattern consistent with a range set by the brain to protect normal functions of organs such as the heart and kidney.  The analysis is based upon 19,151 subjects studies in 62 previously-published surveys and reflects the differing “food environments” of 33 countries. The data reported documents that humans have a habitual sodium intake in the range of 2800 to 4600 mg/day with an average of 3600 mg/day. Currently, the U.S. consumes an average of about 3,500 mg/day.

The McCarron et al study ignores any health consequences of salt reduction.  It questions whether policy or persuasion affect salt intake.  If physiology controls, as Dr. Geerling outlined in his paper last year, “Central Regulation of Salt Appetite” in the journal Experimental Physiology,[vi] then it should be “back to the drawing board” for the DGAC since substituting low-sodium substitutes for customarily-consumed food products will only result in consumers’ adding calories to their diets, not subtracting sodium.  In fact, that has been what has been happening since the Dietary Guidelines began in 1980 – the ratio of sodium-to-calories has declined as grocery stores made available thousands of new, salt-reduced products which they and the Guidelines have promoted as healthy.  While sales of these low-sodium products have increased, sodium levels have remained unchanged and the end result has been an increase in food consumption and the calories that have accompanied that development.

 The study confirms the conclusion of renowned Swedish researcher Björn Folkow who described a “hygienic safety range” for sodium of 2,300 mg to 4,600 or even 5,750 mg/day.[vii]  If the McCarron et al study is confirmed, it would show that the entire current strategy to reduce dietary sodium below these natural levels is unachievable.

We renew our appeal that the 2010 Guidelines drop the Guideline on salt/sodium altogether or, at the very least, reassert the pre-2000 Guidelines’ endorsement of “moderation” since that would seem compatible with the evidence.  We further recommend that the report of the DGAC express disappointment that there has been no follow-up on the 2005 DGAC identification of a “research need” for study of the health outcomes of salt reduction (the only controlled trial was done outside the U.S.).  Finally, we recommend that the DGAC report embrace the recommendation of the McCarron et al study that further research be undertaken to determine if salt intake is a neurally-directed appetite impervious to policy diktat or, as had been previously assumed, a conscious consumer choice amenable to education or, more radically, re-engineering the food supply. 

Sincerely,

Richard Hanneman

President