Disclaimer: I am not a doctor. This is provided for information only. Please consult your health care provider before starting or stopping a treatment plan.
The Brewer Diet, created by Dr. Tom Brewer starting in the 1960s, claims to be a 100% prevention/cure for preeclampsia. This diet is very popular in the natural birth community. After all, what could be more natural than eating healthy? But how does this diet stand up to research? Does it live up to its claim to prevent PE?
In the 1960s, common obstetric practices and treatments for PE involved many things we now know are harmful, things Dr. Brewer spoke out against. He was correct about those poor practices. He also was correct that eating a quality diet during pregnancy is important for the health of both mother and child. I give him credit for that.
Dr. Brewer believed PE was entirely due to poor nutrition, in particular a lack of dietary protein. In fact, he was so convinced of the role of nutrition in the development of PE, he renamed the condition Metabolic Toxemia of Late Pregnancy, or MTLP.
After spending a number of hours over several days reading the primary websites dedicated to the Brewer diet, I still have little understanding of his basic theory. The gist of it is that the body needs protein to increase blood volume enough to sustain a pregnancy. Without adequate dietary intake, blood volume cannot keep up with the demands of the pregnancy, triggering the cascade of symptoms. How he believed this happens, it is not clear. His own research was not peer-reviewed, and I can find no outside research to support this theory, either in his website's own bibliography or in a search of PubMed.
Considering Dr. Brewer claimed a 100% success rate, it would be reasonable to ask, has any woman followed the Brewer Diet and gotten PE anyway? A search of the Preeclampsia Foundation's forums quickly shows there are many women who have, some of them quite severely. But according to this website, the answer is no, there has never been a woman who *correctly* followed the Brewer Diet and got sick anyway. There are only women who *think* they were following the diet, but they couldn't possibly have followed it correctly. Therefore, their experiences do not count as a failure of the diet.
Dr. Brewer himself said in his Aphorism No. 5, "The well-fed, well-salted, well-watered, NON-DRUGGED pregnant lady often develops water retention ("edema" or "oedema") and blood pressure rise (”hypertension”) and protein in her urine ("albuminuria") and "excessive weight gain" which are mistakenly diagnosed as "pre-eclampsia."" In other words, if a woman who is not on his diet has these symptoms, she has PE, but if she has the exact same symptoms while on his diet, it's just a normal part of pregnancy? Um, no. It's PE, and it's dangerous, even more so because a woman might not get the treatment she desperately needs because she's been told her symptoms are normal.
Then there's this claim of "mistaken diagnosis." If a woman has symptoms of PE but is well-nourished to Dr. Brewer's standards, it must not be PE but rather another condition that causes the same symptoms. Um, a condition exactly like PE? That causes the exact same symptoms? But NOT PE? Because, again, it couldn't be the diet that failed. It must be this mysterious Not-PE condition. Hm, could this be a case of Observer's Bias?
(Might I point out that ANY treatment plan can claim a 100% success rate if one simply refuses to acknowledge the failures.)
Another good question to ask would be, has any woman NOT followed the Brewer Diet and NOT gotten PE? And the answer is of course! Every year around the world, hundreds of millions of pregnant women eat a diet that does not meet Dr. Brewer's standards, yet without getting PE. This can range from women in America who eat processed junk and fast food, to women in famine-stricken Africa who do not get enough calories, period, let alone 100g of protein, to vegans who eat a generally healthy diet overall but not quite "perfect". Why do these women NOT get PE when women who followed (or "thought they were following") the Brewer diet do? Clearly, there must be more to it than diet alone. But once you acknowledge that something else can be in play, Dr. Brewer's theories fall apart.
Oh, but maybe it's similar to Type II Diabetes. One must have a predisposition for the condition. If you don't have that predisposition, you can eat whatever crap you want and be fine regardless, but if you DO have the predisposition, you must be very careful about what you eat. If this were true, you would expect to find that women with the worst diets have the highest rates and most severe cases of PE, while those who have generally good (but not quite perfect) diets would have the fewest and mildest cases. But the largest US study on PE and diet ever done (looking specifically at calcium, not protein, but with detailed diet evaluations of all participants) found no difference in the protein intake among those who did and did not get PE, nor did they find any difference in the PE rates among women with poor, fair, and good diets.
But Dr. Brewer was right about those bad obstetric practices back in the '60s. And he was right that traditional treatments for hypertension, in particular salt restricion, wouldn't help (because hypertension is merely a symptom, not the primary problem). So why couldn't his diet theory also be correct?
Considering what we now know about the role of sFlt1 in the cascade of symptoms, his dietary protein theory just doesn't make sense. Oh, but there's an answer for that, too. Just because all women with PE have elevated sFlt1 and no woman without PE has elevated sFlt1, that doesn't mean sFlt1 has anything to do with causing PE. No, if anything it was poor diet that caused the elevated sFlt1, even though women without PE who eat a poor diet don't have elevated sFlt1, and women with a good diet and PE do. I've said it before, I'll say it again: Observer's Bias.
Oh, but what about all the women who follow the Brewer Diet and don't get PE? Who are true believers that it helped them? Well, 90% of women will never get PE whether they follow the diet or not. It doesn't mean the diet saved them. But what about women who got PE the first time around, then discovered and followed the diet, and didn't get PE the second time around? Again, most women who get PE only get it once. This anecdotal "data" doesn't prove it works.
Can I say with certainty that the Brewer Diet doesn't work at all? No, I can't. PE is a very complex condition, and we have a long way to go to unravel all the risk factors that go into it. There may be some women out there for whom the Brewer Diet can make the difference. But it DOES NOT live up to its claim of 100% prevention/cure. It merely ignores failures as either "normal", "misdiagnosed", or a failure of the woman who "didn't follow it correctly".