Each day I see women with Endo who say to me they are scared and confused about what to eat. Can they have fats, if so what are the best fats and how much? Now while it isn’t black and white, unfortunately there are still some grey areas, there has been research into this topic and we do know that there are correlations between certain types of fats and endo.
A staggering 1 in 10 women today have endometriosis. Prevention and or management can occur we know through diet. There is a growing body of literature suggesting a relationship between what one eats and their symptoms associated with endometriosis.
Health professionals believe that diet may influence and contribute to the following areas for endometriosis:
smooth muscle contractility
For example, double-blind crossover study of fish oil supplementation showed a significant reduction in dysmenorrhea (Harel et al., 1996). Deutch, 1995, found that menstrual pain increased as intake of alpha-linolenic acid decreased.
Specific studies focusing on diet and endo development are still limited, and more needs to be done, if we are going to reduce the incidence of endometriosis.
What we do know is the development of endometriosis can be affected based on the type of fat one eats and their red meat consumption.
Missmer et al (2010), found that the type of fat you eat has a strong correlation with the development of endometriosis.
In a large cohort study, the USA based study group followed 586 153 premenopausal women; which included 1199 cases of laparoscopically confirmed endometriosis. Using Food Frequency Questionnaires, they assessed the cumulative averaged fat intake by studying the results completed on three diet questionnaires (1991,1995,1999).
Total fat intake was not associated with endometriosis. But there was the suggestion of an increased risk of endometriosis with animal fat intake. Women in the upper fifth quartile of animal fat intake had a 20% greater risk of endometriosis compared with those in the lowest fifth quartile.
Intake of trans-unsaturated fats was associated with a higher risk of endometriosis. This association became stronger when protein (i.e. animal meats containing fat) and other types of fat were also eaten, estimating the risk of endo increases as one eats more trans-unsaturated fat at the expense of carbohydrates
There was a suggested increased risk of endometriosis with animal fat consumption. The study found the endo risk increased risk nearly 80% with palmitic acid intake (the type of fat found in red meat; and chicken skin)
The intake of long-chain omega-3 fatty acids was associated with a 23% lower risk of endometriosis.
The study also looked at the effects of consuming one specific type of fat instead of another. They found that if participants consumed an additional 1% of energy from omega-3 fatty acids (e.g. increasing from 1 to 2% of total energy intake) rather than from saturated, monounsaturated or omega-6 polyunsaturated fats, there was approximately 50% lower risk of endometriosis, although none of these estimates reached statistical significance.
Interesting, in the results, the authors write that when 1% of energy came from trans fats rather than from any other type of fat there was a significantly higher risk of endometriosis.
So, what are the food sources of omega-3s and trans fats the nurses in this study were eating to have this effect? Well the major dietary contributors to long-chain omega-3 fatty acids were salad dressing, tuna and dark fish. The major contributors to trans-unsaturated fatty acids were commercially brought fried foods, margarine and crackers. The study doesn’t mention supplementation; nor how much omega 3s needs to be consumed to see benefit.
To evaluate red meat consumption and endo, we look to Yamamoto (2018) study. They also used the nurses study but for longer and followed the 115 429 premenopausal women for 20 years (1991-2013), to evaluate the association between intake of red meat, poultry, fish and seafood on the risk of laparoscopically-confirmed endometriosis (3800 cases).
From their study, we learn that intake of red meat, either as processed or unprocessed, is a major culprit in promoting endometriosis risk. Replacement of red meat with fish, shellfish or eggs was associated with lower risk of endometriosis.
A number of important points are worth considering from Yamamoto et al.’s study.
First, the significant increase in endometriosis risk associated with red meat was found from comparing women consuming ≥2 servings per day (equivalent to 14 servings or more per week) with women consuming ≤1 serving per week; the latter effectively being non-red meat eaters. Interestingly, even 2–4 servings per week caused a modest increase in endometriosis risk, suggesting that limiting red meat consumption to less than once weekly is best.
Second, the study indicated that women with the highest red meat consumption (and hence, greater risk for endometriosis) were more likely to be overweight or obese and had greater caloric intake.
What can we draw from these two studies?
- That diet does have a role in endometriosis development. In reading both these two large cohorts, both authors discussed the need for more, and the limitations on current other research in this field.
Reducing red meat (both studies confirmed this for us) is beneficial to reducing endometriosis risk
Red meat is a viable food, and it does provide us with many nutrients. Yamamoto did not conclude no read, just to reduce its occurrence. So when eating red meat; try and buy grass feed beef from a local butcher who knows his cattle. Cut away any visible fat and limit to once a fortnight
It is really important to limit takeaway foods, margarines, crackers, cakes, and store brought foods which can contribute trans fats to the diet. When buying package foods, read your labels. If saturated fats are >1g / 100g or if there is any presence of trans fats, pop the product back on the shelf.
Add in omega-3s. Supplementation wasn’t assessed; so even if you do eat oily fish, I would still look at taking a good quality omega-3 supplement. Marine omega-3s are shown to be stronger sources of omega-3s for our bodies, and these include Atlantic salmon, sardines, tuna, mackerel. The ideal amount would be 2 Atlantic salmon nights a week each week.
Believe in your food. It can be hard to see, as the benefits of making those healthy dishes feels so far away. But making these changes sews, even the smallest ones, the seeds for improved health.
Hum Reprod. 2010 Jun;25(6):1528-35. doi: 10.1093/humrep/deq044. Epub 2010 Mar 23.
A prospective study of dietary fat consumption and endometriosis risk.
Missmer SA1, Chavarro JE, Malspeis S, Bertone-Johnson ER, Hornstein MD, Spiegelman D, Barbieri RL, Willett WC, Hankinson SE.
A prospective cohort study of meat and fish consumption and endometriosis risk.
Yamamoto A1, Harris HR2, Vitonis AF3, Chavarro JE4, Missmer SA5.
Am J Obstet Gynecol. 2018 Aug;219(2):178.e1-178.e10. doi: 10.1016/j.ajog.2018.05.034. Epub 2018 Jun 2.