Correspondence
More on Coronary Heart Disease: The Dietary Sense and Nonsense
N Engl J Med 1994; 331:614-616September 1, 1994
- Article
To the Editor:
In his review of Coronary Heart Disease: The Dietary Sense and Nonsense (March 31 issue),1 Dr. Stone writes about the report of one very large review2 that it is “truly critical and comprehensive.” However, that report, in dealing with migration studies, omits those that do not fit the diet-heart hypothesis -- for example, the studies by Day et al.3 and Stanhope et al.4 This omission is deliberate and explicit (“Only representative publications have been cited here” [page 178]2) and not due to limitations in the number of references, since some 1000 references are cited in this section. It is doubtful whether such selectivity can be labeled “critical and comprehensive.”
Dr. Stone writes that the Oslo Study Diet and AntiSmoking Trial “showed the importance of a cholesterol-lowering diet low in saturated fat in reducing both morbidity and total mortality from coronary heart disease.” The study did not show that5. In addition to a drop in saturated-fat intake, cigarette consumption dropped by half and weight went down by an average of 5 kg, without any concomitant reduction in energy intake; thus, the participants must have started exercising. It is not obvious that of these several interventions, a reduction in saturated fat played any part. The conclusion of the investigators differs from that of Dr. Stone: “If this had been a diet trial only, the difference in MI incidence between the two groups would probably not have reached statistical significance.”
5 ReferencesOlov H. Holmqvist, Ph.D.
Swedish Meat Research Institute, S-244 24 Kavlinge, Sweden1
Stone NJ . Review of: Coronary heart disease: the dietary sense and nonsense -- an evaluation by scientists. N Engl J Med 1994;330:943-944
Full Text | Web of Science | Medline2
Committee on Diet and Health, Food and Nutrition Board, Commission on Life Sciences, National Research Council. Diet and health: implications for reducing chronic disease risk. Washington, D.C.: National Academy Press, 1989:159-258.
3
Day J ,Carruthers M ,Bailey A ,Robinson D . Anthropometric, physiological and biochemical differences between urban and rural Maasai. Atherosclerosis 1976;23:357-361
CrossRef | Web of Science4
Stanhope JM ,Sampson VM ,Prior IA . The Tokelau Island Migrant Study: serum lipid concentration in two environments. J Chronic Dis 1981;34:45-55
CrossRef | Medline5
Hjermann I ,Velve Byre K ,Holme I ,Leren P . Effect of diet and smoking intervention on the incidence of coronary heart disease: report from the Oslo Study Group of a randomised trial in healthy men. Lancet 1981;2:1303-1310
CrossRef | Web of Science | Medline
To the Editor:
In the guise of a review of George Mann's book, Stone pitches the diet-heart hypothesis. Since Muldoon et al. have shown that all properly controlled trials of cholesterol lowering have only raised the death rate,1 Stone resorts to three ploys to muddy the waters.
First, he cites the Oslo trial, in which subjects had 45 percent less tobacco use, and terms it “one of the best clinical diet trials... which showed the importance of a cholesterol-lowering diet,”2 when in fact, the Oslo trial was not designed to show a benefit of diet alone3.
Second, Stone changes the subject to the regression of atheroma, whereas Mann questions the safety of cholesterol-lowering diets. Those of us who have published angiographic evidence of atheroma regression4 are well aware of the increased risk of death associated with these diets. However, since the trials are kept short, this excess mortality may be small. For example, the San Francisco Lifestyle Trial reported regression during a study period of one year; the controls were sedentary, and about 20 subjects exercised and lost 20 pounds on the “regression diet.” One subject died, and no controls died5.
Clearly, so-called regression diets can be lethal; we have reported many unexplained sudden deaths among marathon runners experimenting with such diets6.
Third, Stone sidesteps Mann's premise that the public is being oversold on the “cholesterol war.” Stone confines his attack not to the content of the book but to its tone of “anger,” as he terms it. I fully agree with Mann, and my colleague and I have projected that billions of dollars and millions of lives will be wasted if the cholesterol war continues7. Of this, the public is certainly not aware.
7 ReferencesThomas J. Bassler, M.D.
27558 Sunnyridge Rd., Palos Verdes, CA 90274-40411
Muldoon MF ,Manuck SB ,Mathews KA . Lowering cholesterol concentrations and mortality: a quantitative review of primary prevention trials. BMJ 1990;301:309-314
CrossRef | Web of Science | Medline2
Hjermann I ,Velve Byre K ,Holme I ,Leren P . Effect of diet and smoking intervention on the incidence of coronary heart disease: report from the Oslo Study Group of a randomised trial in healthy men. Lancet 1981;2:1303-1310
CrossRef | Web of Science | Medline3
Vandenbroucke JP ,Hofman A . Cholesterol, smoking, and the Oslo Study. Lancet 1982;1:503-503
CrossRef | Web of Science4
Bassler TJ . `Regression' of atheroma. West J Med 1980;132:474-475
Medline5
Ornish D ,Brown SE ,Scherwitz LW , et al. Can lifestyle changes reverse coronary heart disease? The Lifestyle Heart Trial. Lancet 1990;336:129-133
CrossRef | Web of Science | Medline6
Bassler TJ . Hazards of restricted diets. JAMA 1984;252:483-483
CrossRef | Web of Science | Medline7
Bassler TJ ,Bassler TJ Jr . Long-term mortality after primary prevention for cardiovascular disease. JAMA 1992;267:2183-2183
CrossRef | Web of Science | Medline
To the Editor:
Dr. Stone takes me, the author of the chapter on diet, serum cholesterol, and coronary heart disease, to task for allegedly claiming that the quotation, “The diet-blood cholesterol-CHD [coronary heart disease] literature has seldom been reviewed critically and never thoroughly,” was taken from the Diet and Health Report1. He goes on to say, “Would that the author of the chapter had read the report more carefully: it is truly a critical and comprehensive review of this issue. (The Surgeon General's Report on Nutrition and Health from 1988... is likewise very thorough.)”
Would that Dr. Stone had read my chapter more carefully. It specifically attributes the quotation to Smith and Pinckney,2 not to the report on diet and health1. Dr. Stone obviously misread my footnote 2 as footnote 12. Anyone who reads the report by Smith and Pinckney2 must conclude that their statement is correct and that the Diet and Health Report and the Surgeon General's Report are substantively flawed with respect to their discussion of diet, serum cholesterol, and coronary heart disease.
I am pleased that Dr. Stone recognizes that “the chapter does present a detailed discussion of the effect of trans fatty acids in the diet and their putative role in promoting coronary heart disease in this country over the past century.” However, Dr. Stone further states that “the tone of the chapter... suggests that this is an issue that mainstream medicine has shunned; in fact, articles and editorials dealing with this important subject continue to be published in leading medical journals.” Before the 1990 seminal article by Mensink and Katan,3 there was a dearth of reports on trans fatty acids in leading medical journals; their article opened the floodgates to what even Dr. Stone recognizes as “this important subject.”
Dr. Stone errs in his statement that “rates of coronary heart disease have been falling in the U.S. population.” Only age-adjusted mortality rates have fallen; incidence rates have risen. In simple terms, coronary heart disease has been developing in more people while the intake of vegetable fats and oils has been increasing; the treatment approaches (e.g., coronary bypass surgery and angioplasty) have caused a decrease in the mortality rates, mostly by extending life and permitting patients with coronary heart disease to grow older and move into higher age brackets.
3 ReferencesMary G. Enig, Ph.D.
Enig Associates, 11120 New Hampshire Ave., Silver Spring, MD 20904-26331
Committee on Diet and Health, Food and Nutrition Board, Commission on Life Sciences, National Research Council. Diet and health: implications for reducing chronic disease risk. Washington, D.C.: National Academy Press, 1989.
2
Smith RL, Pinckney ER. Diet, blood cholesterol, and coronary heart disease: a relationship in search of evidence. Santa Monica, Calif.: Vector Enterprises, 1988.
3
Mensink RP ,Katan MB . Effect of dietary trans fatty acids on high-density and low-density lipoprotein cholesterol levels in healthy subjects. N Engl J Med 1990;323:439-445
Full Text | Web of Science | Medline
Author/Editor Response
Dr. Stone replies:
To the Editor: I certainly did not intend to suggest that the statement, “The diet-blood cholesterol-CHD [coronary heart disease] literature has seldom been reviewed critically and never thoroughly” came from the Diet and Health Report. Since Dr. Enig did cite this report in her 12th footnote (as I correctly noted), I still find it hard to understand how she could find it anything other than critical and comprehensive.
Her statement that “only age-adjusted mortality rates have fallen; incidence rates have risen” is not supported by a careful community-based, multihospital study from Worcester, Massachusetts,1 which used validated data to document a decrease in incidence rates for acute myocardial infarction and out-of-hospital deaths among both men and women between 1975 and 1988.
The Oslo Diet and AntiSmoking Trial deserves mention in any discussion of diet and coronary heart disease. It was a large randomized clinical trial that clearly showed a significant reduction in total cholesterol in the intervention group as compared with the control group2. Statistical analysis showed “that the reduction in incidence in the intervention group is correlated with the reduction in total cholesterol and to a lesser extent with smoking reduction.”
I would ask Dr. Bassler to reconsider his thoughts on the safety of diet. Meta-analyses must be interpreted cautiously, because the exclusion criteria are often not specific enough to avoid mixing studies that vary in the quality of their design and the intervention attempted3. The one subject who died in the trial by Ornish and colleagues was reported to have greatly exceeded the recommended exercise, not the dietary limits4.
4 ReferencesNeil J. Stone, M.D.
Northwestern University School of Medicine, Chicago, IL 606111
Goldberg RJ ,Gorak EJ ,Yarzebski J , et al. A communitywide perspective of sex differences and temporal trends in the incidence and survival rates after acute myocardial infarction and out-of-hospital deaths caused by coronary heart disease. Circulation 1993;87:1947-1953
Web of Science | Medline2
Hjermann I ,Velve Byre K ,Holme I ,Leren P . Effect of diet and smoking intervention on the incidence of coronary heart disease: report from the Oslo Study Group of a randomised trial in healthy men. Lancet 1981;2:1303-1310
CrossRef | Web of Science | Medline3
LaRosa JC . Cholesterol lowering, low cholesterol, and mortality. Am J Cardiol 1993;72:776-786
CrossRef | Web of Science | Medline4
Ornish D ,Brown SE ,Scherwitz LW , et al. Can lifestyle changes reverse coronary heart disease? The Lifestyle Heart Trial. Lancet 1990;336:129-133
CrossRef | Web of Science | Medline
