Biblical counsel on diet is not as clear-cut as is sometimes claimed. True enough, the “Edenic” diet was clearly vegan; seed bearing plants and fruit bearing trees, Gen 1:29. However, the Bible touches upon dietary matter in many different ways and under a variety of circumstances.
As an example, only four verses earlier the author of Genesis records the creation of “herd” or “domesticated” animals behemah, as well as wild ones chayeh (Gen 1:24, 25). “Herd” animals might conceivably have been limited to beasts of burden but this is unlikely since Abel brought offerings to the Lord from his flocks and herds shortly after the expulsion from Eden; horses and donkeys are not suitable for sacrifice—they are ritually unclean. Thus, the “herd” or “domesticated” animals of the original creation, could well have added milk and perhaps eggs to the “Edenic” diet—a true lacto-ovo-vegetarian diet!
Meat is first recorded as being allowed after the Flood but the “Children of Promise” were herdsmen as far back as Abel and wealth among the ancestors of the Hebrews was reckoned in the size of the herds a patriarch possessed. After all, Esau’s favorite dish featured the meat of young goats (Gen 27:9). Even God, on occasion, claims as his own “the beast chayeh of the forest as well as the cattle behemah on a thousand hills” (Psa. 50:10). In short; there is scant indication that a vegetarian diet was even an option for the early Hebrews. What is clear, however, is that the Bible advocates simplicity and moderation in all things, particularly in dietary matters.
Other than simplicity in the food that we eat and counsel to eat and drink in moderation the only other formal dietary advice given by the Bible is phrased in prohibitions—the list of clean and unclean meats in Leviticus and Deuteronomy. Pork is clearly prohibited but the list is otherwise not a great deal of help since it approves grasshoppers, locusts and beetles! (Lev. 11:22)
So where does that leave us today in the pursuit of “truth” in dietary matters? Or, more broadly, where does that leave us in the pursuit of “truth” generally. Dietary decisions are both frequent (three times a day for most of us) and meaningful—they likely affect how long we will live. Very few of our decisions are more frequent or more meaningful than that. Thus, a consideration of how we decide dietary questions may give us insight into how we make meaningful decisions generally; that would be a most useful insight. First, it should be pointed out that dietary decisions are, or should be, scientific ones—decisions based on empirical (objective, repeatable) data. Scientific decision-making has been analyzed for several centuries by philosophers of science. Let’s briefly explore what some of them have had to say on the matter.
We’ll start with the idea of inference. A nutritionist studies a large number of people and determines that those who eat lots of dietary fiber rarely have a painful inflammation of the colon called diverticulitis. They note that high dietary fiber correlates with low diverticulitis and low dietary fiber correlates with more of the disease. From this inverse correlation they infer that more dietary fiber in some way decreases the chances of having diverticulitis. Given this correlation and the inference that nutritionists have drawn, the dietary question for each of us now becomes “Should I eat more fiber; is this a real scientific finding?” In the mid-eighteenth century, Scottish philosopher David Hume pointed out that scientific inference never achieves certainty. If the first thirty swans we see are white we may infer that “all swans are white”. While this is a reasonable inference we can never be sure that it is correct, for the discovery of even a single black swan will upset our inference.
Two hundred years later the British philosopher Karl Popper tried his hand at the matter and proposed that the method by which science arrived at “truth” was for a scientist to propose a theory—to state that something was “true” — and then immediately to set about trying to disprove it. Only after failing repeatedly in that effort could a scientist claim “truth” for the theory and even then it would always be in danger of being disconfirmed by some future scientific discovery. Popper’s approach to decision making is sometimes called the “falsification approach”.
“Not so fast”, said W. V. O. Quine, a Harvard philosopher who died recently. “That is not the real world you are talking about”. Quine’s take is approximately as follows. We accept as “true” a proposition that has a reasonable amount of empirical evidence going for it and — here is where it gets tricky — does not require us to abandon a lot of other conclusions that we have already accepted as true. Quine’s approach is sometimes described as “scientific holism”.
How does this approach play out in terms of what we choose to eat? We are quite likely to add some vitamin D to our daily diet if the scientific evidence runs strongly in favor of the benefit of vitamin D provided taking a daily supplemental dose of vitamin D does not require us to abandon other strongly held beliefs — other dietary matters that we have previously decided are “true”.
Quine’s observations make a certain amount of sense. SDAs have been warned about the dangers of tea and coffee for many years. There are many research reports in the recent scientific literature suggesting that drinking green tea has many health benefits including some protection from prostate cancer. Accepting these scientific reports as “true” and starting to drink green tea is not even possible for many SDAs because it would require abandonment of a life-long dietary program which strictly banned tea and coffee.
I recently suggested to a friend suffering from prostate cancer that adding several cups a day of green tea to his diet would be highly unlikely to hurt and might, just might, slow the progress of his disease. His reply was, “I haven’t spent my life avoiding tea to start drinking it now”. For him the inclusion of tea would have required an unacceptably radical alteration of a “good to eat” list developed over a lifetime. That was a change he was incapable of making—too many other “truths” that he had incorporated into his world view would have been disturbed.
This brings us to the ongoing Adventist Health Study-2. This is a very comprehensive study and it will produce a correspondingly large amount of data. From this study will come correlations that will suggest — in some cases no doubt, strongly suggest — that those who follow certain dietary patterns are likely to suffer less cancer, less heart disease, less stroke etc. and live longer. Which of the changes indicated in this way will be widely adopted by rank and file members of the Adventist Church? If Quine is right the changes adopted will be those that do not require reshuffling of traditional Adventist beliefs about what is fit and what is not fit to eat.
For the most part the changes endorsed by a scientific study of 96,000 SDAs will be non-controversial but there is the virtual certainty that some dietary changes will prove too difficult for some Adventists to stomach (sorry about that!).
Why do I even bring this matter up? Because, just as plans for distributing money are best worked out before any money is available, so philosophical challenges are best thought out before action is required. And in matters dietary any decision is going to be much more than theoretical agreement with a philosophical idea. In matters dietary we act upon our philosophical conclusion—we eat or don’t eat what we believe is health promoting or health damaging.
The early, and still very preliminary returns from the health study suggest that a vegan diet is not as beneficial as a lacto-ovo-vegetarian one — vegans die earlier — in fact, they die at a rate that is only slightly less rapid that omnivore Adventists (who eat meat and seafood, etc). Now I must stress that the data are not yet statistically valid — there are only about 4,000 vegans registered in the study so it will be a while yet before the data set is large enough for statistical validity — but these early returns at least raise the possibility that the full set of data may not confirm the confidently expected (by vegans) superiority of a vegan diet. What then? Will those who have adopted this dietary pattern at considerable expense and bother (and who may have followed it for a lifetime) abandon this diet? I would guess not. I would expect that Quine is right and that too many other firmly held beliefs would have to be abandoned in order for that to occur.
Obviously, this particular philosophical/dietary conundrum may never come to pass. Additional data, as it comes in over the next few years, may lower the all-cause mortality of vegans into the range of the lacto-ovo-vegetarians. While this is certainly possible it is unlikely for two reasons.
First, if the data from earlier studies on Adventists and other vegetarians is examined closely, the same higher, all-cause mortality rates are associated with vegans in those studies also. However, all of those studies had too few vegans registered to achieve statistical rigor on the relative death rates of vegans. This will not be a problem with the Adventist Health Study-2 as there are several thousand vegans registered.
Secondly, there is, at present, no reason to suspect that the early returns from the AHS-2 are skewed such that the average mortality rate will drop significantly as more data comes in. The usual behavior of this sort of data is that the average mortality stays approximately the same as the study matures and the confidence limits narrow down.
So how do we decide “truth” in matters of diet? If the philosophers of science are right it is a process that requires good evidence and something more—that something more is a requirement that the new “truth” not upset too many of our previously held beliefs. I think that a moment’s reflection will disclose that we probably operate that way in other areas of our lives too; not just in decisions about what, and what not, to eat.
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 From a platform presentation made by Dr. Gary Fraser, lead scientist on the Adventist Health Study-2 at the Adventist Nutrition Conference, 2008. DVDs of the presentation are available from Sigma Audio/Video Associates, P.O. Box 51, Loma Linda, CA 92354
 For those interested in the preliminary statistics, SDAs classified as lacto-ovo-vegetarians are showing an all-cause mortality (death-rate) that is only 75% that of the omnivores in the study. Lacto-ovo-vegetarians who also eat fish are doing even better at 72%. The all-cause mortality of vegans is essentially indistinguishable from that of omnivore SDAs (~95%).
 See “Risk Factors and Disease among Vegans”, chapter 13, in Diet, Life Expectancy, and Chronic Disease: Studies of Seventh-day Adventists and Other Vegetarians (New York: Oxford University Press), pp. 237, 238.
This is a companion discussion topic for the original entry at http://spectrummagazine.org/node/2424