# Uterine Fibroids

Category: Conditions

Also known as: fibroids, leiomyoma

Uterine fibroids are benign tumors of the uterine smooth muscle whose growth is fundamentally driven by a hormonal environment of estrogen dominance secondary to low thyroid function. Peat argued that normalizing thyroid is the single most effective intervention, as adequate…

10 passages · 2 authors · 1996–2022 · Most-cited: [Ray Peat](https://bioenergeticoracle.com/md/voices/ray-peat/index.md)

Canonical page: https://bioenergeticoracle.com/concepts/uterine-fibroids

## Synthesis

**Uterine fibroids** are benign tumors of the uterine smooth muscle whose growth is fundamentally driven by a hormonal environment of **estrogen dominance** secondary to *low thyroid function*. [Source 3, 6] Peat argued that normalizing thyroid is the single most effective intervention, as adequate thyroid hormone lowers estrogen while simultaneously increasing the activity of enzymes that break down fibrotic tissue. [Source 4, 5] He documented a case in which a woman with a tennis-ball-sized fibroid blocking her fallopian tubes achieved complete resolution and became pregnant within months by taking enough thyroid to maintain a resting pulse of 110 beats per minute, which suppressed her estrogen and visibly shrank the tumor on monthly ultrasounds. [Source 1, 4, 7]

The pathophysiology of fibroids is a specific instance of a generalized fibrotic process driven by *excitotoxicity* and energy failure. Peat described fibrosis as an abnormal progression of extracellular matrix formation involving increased collagen volume, density, and pathological cross-linking, analogous to the stiffening of aging tissues. [Source 2] Estrogen is a powerful promoter of this process; chronic estrogen treatment produces fibrosis of practically all tissues, and the fibrotic tissue later becomes a site for cancer development. [Source 9] The condition is inseparable from hypothyroidism, which creates a leaky, edematous cellular state and shifts the ratio of estrogen to progesterone and androgens unfavorably high. [Source 2, 3] This same mechanism underlies related conditions including endometriosis and breast fibrocystic disease. [Source 6]

Several nutritional and hormonal factors directly oppose the fibrotic process. **Vitamin D** and **calcium** are recognized as important anti-fibroid factors, and Dinkov has highlighted evidence that maintaining vitamin D blood levels above 30 ng/mL may shrink or remove fibroids, with synergism between vitamin D and bioidentical **progesterone** allowing for lower effective doses of each. [Source 4, 10] Progesterone itself has the strongest antifibromatogenic action among the steroids, working partly through its effects on collagenase and fibroblasts and partly by displacing estrogen from tissues. [Source 9] Peat noted that progesterone was tested and does work for shrinking fibroids, though it functions partly through supporting thyroid activity. [Source 5] Magnesium, taurine, and niacinamide also have protective functions that can help reduce or reverse inflammatory and fibrogenic processes. [Source 8]

Dietary strategies center on minimizing substances that promote the nitric oxide pathway and maximizing protective nutrients. Avoiding **polyunsaturated fats** helps maintain proper urea formation rather than shifting arginine metabolism toward nitric oxide, which is involved in fibrotic processes. [Source 6, 8] Protein deficiency is thrombogenic and likely excitotoxic, while excess tryptophan increases serotonin production and excess arginine increases nitric oxide formation. [Source 8] The amino acid **glycine**, which constitutes a very high percentage of collagen, serves as an inhibitory transmitter and has remarkable protective activities against toxins. [Source 8] Peat recommended blood testing to check thyroid, estrogen, and vitamin D status as a starting point for addressing fibroids, and emphasized that keeping carbon dioxide production high by optimizing thyroid function is protective against the serotonin and nitric oxide pathways that drive fibrosis. [Source 4, 8]

## People also ask

### How does low thyroid function contribute to uterine fibroid growth?

Peat argued that hypothyroidism creates estrogen dominance by lowering the body's ability to clear estrogen, while also reducing the activity of enzymes that break down fibrotic tissue, directly driving the growth of fibroids.

### Can vitamin D and progesterone work together to shrink fibroids?

The corpus describes evidence that maintaining vitamin D levels above 30 ng/mL may shrink fibroids, and that bioidentical progesterone synergizes with vitamin D, allowing lower effective doses of each to oppose the fibrotic process.

### Why is avoiding polyunsaturated fat recommended for fibroids?

Peat's framework suggests that avoiding polyunsaturated fats helps maintain proper urea formation, preventing arginine metabolism from shifting toward nitric oxide production, which is involved in driving fibrotic processes.

## Related concepts

- [Hashimoto's Thyroiditis](https://bioenergeticoracle.com/md/concepts/hashimoto-s-thyroiditis/index.md)
- [Acne](https://bioenergeticoracle.com/md/concepts/acne/index.md)
- [Fish Oil](https://bioenergeticoracle.com/md/concepts/fish-oil/index.md)
- [Benign Prostatic Hyperplasia (BPH)](https://bioenergeticoracle.com/md/concepts/benign-prostatic-hyperplasia-bph/index.md)
- [Cataracts](https://bioenergeticoracle.com/md/concepts/cataracts/index.md)
- [Chronic Fatigue Syndrome](https://bioenergeticoracle.com/md/concepts/chronic-fatigue-syndrome/index.md)

## Cited passages

Passage numbers match the `[Source N]` markers in the synthesis above.

### Source 1 — One Radio Network: Patrick Timpone: Dr. Peat Answers Questions Regarding Health, Diet and Nutrition Part 2

Ray Peat · Interview · Jan 1, 2014 · http://www.l-i-g-h-t.com/files/one-radio-network-patrick-timpone-dr-peat-answers-questions-regarding-health-diet-and-nutrition-part-2.mp4

> ## Uterine Fibroids
>
> **Patrick Timpone:** "I'm a follower of Mr. Peat's. I haven't seen anything mentioned about uterine fibroids. What is his suggestion for the best way to get rid of them? Serrapeptase and other enzymes have not worked for me."
>
> **Ray Peat:** I think normalizing thyroid is the best thing. I had an experience with a woman who was about 40 at the time, hadn't had any kids, and wanted to get pregnant. She had a fibroid plugging the end of her uterus by the fallopian tubes about the size of a tennis ball. I explained the physiology to her. She adjusted, taking enough thyroid that she could keep her estrogen level down while keeping the other hormones up. It happens that her pulse averaged about 110 per minute. Her doctor told her she would die from keeping her pulse that fast. But she had an ultrasound every month, and every month that she kept her thyroid at that level, the fibroid shrank. I think she started around March or April, and by August the fibroid had disappeared and she was pregnant.

### Source 2 — Fibrosis: Estrogen, stiffness, excitotoxicity, aging — a problem more general than collagen disease

Ray Peat · Article · 2001

> For example, when a cell is deficient in vitamin E it loses molecules such as ATP and proteins, that diffuse out into the extracellular spaces. When cells are in an energy deficient state, as in hypothyroidism, they are in this leaky, edematous state.
>
> This state of near exhaustion is similar to the "excitotoxic" state that's caused by an imbalance between stimulation and energy production. In the brain, excitotoxins have been found to produce a kind of fibrosis, in which the cells that normally produce the myelin sheath surrounding nerve axons begin producing collagen, and appear to change into a type of cell (Schwann cell) that is not normally found in the brain. The production of collagen seems to be a very basic kind of defensive reaction to excessive stimulation or oxygen deprivation. This makes it possible to see "excitotoxicity" as a general process, that includes the kind of fibrosis and calcification of skin that Hans Selye produced (by combining vitamin E deficiency with heavy metal toxicity and local irritation), as well as the aging of brain cells produced by prolonged estrogenic stimulation.
>
> Scleroderma, like the other "collagen diseases," affects women (during their reproductive years) much more often than men. Retroperitoneal fibrosis, which can seriously damage the kidneys and other abdominal organs, has been compared to uterine fibroid tumors, and it is commonly treated successfully with the antiestrogenic drug, tamoxifen. Tamoxifen has also been used to treat keloids and to prevent abnormal scars in plastic surgery. (I have seen keloids regress quickly following the application of vitamin E with antiestrogenic hormones.) The fibrotic response to the excitotoxic imbalance can be seen in practically all chronic and degenerative diseases.
>
> Fibrosis is an abnormal progression of the normal formation of fibrous material between cells, and it usually involves an increase in the volume of the extracellular material, and an increase in the percentage of collagen in that matrix, and an increased rigidity of the collagen that results from chemical cross-links, that are analogous to the polymerization of a plastic, or the vulcanizing of rubber. Arteriosclerosis is probably the best known medical example of tissue fibrosis, but it's the same phenomenon that makes the meat from an old animal tough and rubbery.

### Source 3 — KMUD Herb Doctors: Uses of Urea (Feb 2015)

Ray Peat · Interview · Feb 20, 2015 · http://l-i-g-h-t.com/files/herb-doctors-uses-of-urea.mp4

> **Ray Peat:** Oh definitely, low thyroid causes the ratio of estrogen to progesterone and androgens to be very high, and both endometriosis, uterine fibroids and also breast fibrocystic disease: all of these go with high estrogen, low progesterone and low thyroid function.
>
> **Andrew Murray:** Caller, is that of help in any way?
>
> **Caller:** Yeah, it does thank you very much.
>
> **Andrew Murray:** You are welcome. If we get a chance here, we will get into the negative effects of estrogen and talk about isoflavones, but we do have a couple more callers. Let’s take this next caller. Caller you are on air and where are you from.
>
> **Caller:** [Severe sleep issues] I heard that tart cherry juice gives sleep, but I haven't tried that. But everything I’ve tried over the counter, medications, nothing helped.
>
> **Andrew Murray:** Dr. Peat, it’s probably an over-adrenaline situation, but how would you best describe to this lady what she could do to get some sleep?
>
> **Ray Peat:** Checking and having a test for thyroid function is important.
>
> **Caller:** My sister has Graves’ disease.

### Source 4 — One Radio Network: Ray Peat with Patrick Timpone — December 21, 2020

Ray Peat · Interview · Dec 21, 2020

> **Patrick Timpone:** Kale is a good food? Kale?
>
> **Ray Peat:** Yeah, as a source of vitamin K in particular, calcium, magnesium.
>
> **Patrick Timpone:** Would you ask Dr. Peat, this is from Helen in Australia, approach to dealing with uterine fibroids, especially when they have grown so much that they're putting pressure on the colon and my bladder. Wow.
>
> **Ray Peat:** Okay. Yeah, having a blood test is important to check your thyroid, estrogen, and vitamin D, calcium and vitamin D. are recognized as very important anti-fibroid factors, along with thyroid. One outstanding example I think illustrates what thyroid can do. A woman in her early 40s hadn't had a child and wanted to, but she had a big fibroid blocking the top of her uterus, blocking both fallopian tubes. I explained how thyroid lowers estrogen while increasing the activity of enzymes that can break down fibrotic tissue. Anyway, she took what her doctor said was a very dangerous overdose thyroid kept her heart rate beating at rest 110 beats per minute that was in the spring she had an ultrasound every month and saw visible shrinking so she stayed with it through the summer and by I think it was September or October she was pregnant the tumor had shrunken visibly every month just by keeping her estrogen under control, by keeping a steadily, slightly above average thyroid activity.

### Source 5 — Your Own Health And Fitness: Thyroid/Progesterone And Diet

Ray Peat · Interview · Nov 12, 1996 · http://www.l-i-g-h-t.com/files/your-own-health-and-fitness-thyroid-progesterone-and-diet -november-12-1996-57-mins.mp4

> **Caller:** What can you do of those?
>
> **Ray Peat:** Thyroid is the basic thing. I have had people get into a slightly hyperthyroid state taking a good balanced thyroid supplement and month by month they have documented that t he thyroid alone is able to shrink the uterine fibroids.
>
> **Layna Berman:** Really without using progesterone?
>
> **Ray Peat:** Yeah, the progesterone was tested and does work but partly it works through the thyroid and the essential thing is to take enough thyroid to get your estrogen way down even below normal for a while.
>
> **Caller:** Where do you go? Do you have to go to doctor?
>
> **Layna Berman:** Yeah, you do, and that’s going to be an interesting argument I don’t even want to hear that argument. Caller, thank you for your call. Good luck.
>
> **Caller:** Thanks.
>
> **Layna Berman:** I actually have heard people just changing in my experience with clients that I’ve had – just changing their diet and getting rid of the grains, getting protein out, getting rid of the beans, getting rid of the soy and getting them on some supplemental progesterone has worked.
>
> **Ray Peat:** Yeah, that’s ultimately the best thing but if they are in a hurry to have a baby or something, they can speed it up with.

### Source 6 — KMUD Herb Doctors: Uses of Urea (Feb 2015)

Ray Peat · Interview · Feb 20, 2015 · http://l-i-g-h-t.com/files/herb-doctors-uses-of-urea.mp4

> **Andrew Murray:** Okay, so we do have three more callers on the line. Let’s move onto the next callers.
>
> **Caller:** My question has to do with breast health. What I would like to ask is that you addressed urea in reference to breast health and particularly fibroids.
>
> **Andrew Murray:** Okay, Dr. Peat did you hear that, the reference is to breast health and fibroids and the benefits of urea.
>
> **Ray Peat:** I don't know of any particular treatments or programs for those with urea, but the diet that favors the formation of urea rather than its antithesis nitric oxide... It happens that the amino acid arginine can either form nitric oxide or urea, and irritants, anything toxic, tends to shift it away from forming urea and going to nitric oxide. So avoiding the polyunsaturated fats helps you maintain the proper amount of urea formation.
>
> **Andrew Murray:** There is plenty of scientific evidence to show that estrogens are actually very damaging and that in terms of breast health and fibroids. Dr. Peat you would agree that estrogen is probably one of the main contributory factors for fibroids.

### Source 7 — One Radio Network: Health & Diet

Ray Peat · Interview · Dec 4, 2013 · http://l-i-g-h-t.com/files/one-radio-network-patrick-timpone-dr-peat-answers-questions-regarding-health-diet-and-nutrition-part-1.mp4

> **Caller:** How many MG per drop of lugols?
>
> **Ray Peat:** I think it’s a few milligrams
>
> **Caller:** I’m a follower of Mr Peats, I haven’t seen anything about uterine fibroids, what is his suggestions for getting rid of them. Peptase and other enzymes have not worked for me.
>
> **Ray Peat:** Normalizing Thyroid is the best thing. I had an experience with a woman who was 40 at the time, and wanted to get pregnant, and had a fibroid plugging the uterus by the fallopian tubes, about the size of a tennis ball, and I explained the physiology to her, and got her confident that she knew what was happeneing, and she adjusted taking enough thyroid to keep her estrogen down while keeping her other hormones up, and it happened that he pulse averaged 110 per minute, and her doctor told her that she would die from keeping her pulse at that level, but she had an ultrasound every month ad every month that she kept her thyroid at that level, the Fibroid shrank. She started in march or April I think, and by August she was pregnant
>
> **Caller:** is a slowe pulse generally better?
>
> **Ray Peat:** No generally it is not

### Source 8 — Fibrosis: Estrogen, stiffness, excitotoxicity, aging — a problem more general than collagen disease

Ray Peat · Article · 2001

> The calorie-restricted diets that slow the aging process reduce the accumulation of the unstable fats and the heavy metals. Vitamin E reduces the vascular leakiness and the free radical peroxidation that are so closely involved in fibrosis. Since serotonin and nitric oxide are involved in these processes, they should be minimized by keeping carbon dioxide production high (by optimizing thyroid function), and by eating proteins that have a safe balance of the amino acids. Too much arginine increases nitric oxide formation, and too much tryptophan increases serotonin production. Too much glutamic acid, aspartic acid, and cysteine can be directly excitotoxic, and the metabolites of cysteine include proinflammatory homocysteine, which can disrupt collagen structure.
>
> Since estrogen is often a promoter of fibrosis, acting in a variety of ways, it should be kept under control by eating enough protein, keeping thyroid function relatively high, and if necessary by using progesterone and other antiestrogenic hormones. A protein deficiency is thrombogenic (clot forming), and probably excitotoxic.
>
> Magnesium, taurine, and niacinamide have many protective functions, and can help to reduce or reverse inflammatory and fibrogenic processes.
>
> [references]

### Source 9 — Progesterone, thyroid, cancer

Ray Peat · Article · 2002

> A.V. Everitt's book on the pituitary and aging mentions some studies that relate to progesterone and aging. Uterine collagen aging, which increases under the influence of estrogen, is lowest in the old rodents that have been bred the most often, and this is probably partly the result of progesterone's action on collagenase and fibroblasts, as well as its ability to displace estrogen from the tissues. Leo Loeb showed that excess estrogen and aging both produced similar increases in collagen. Alejandro Lipschutz found that chronic estrogen treatment produced fibrosis of practically all tissues, and that cancer later developed in those fibrotic tissues. Then he tested various steroids, and found that progesterone had the strongest antifibromatogenic action, and that pregnenolone was next in effectiveness. (Brief intermittent exposures to estrogen didn't produce the harmful effects, and now it's known that progesterone decreases the tissues' retention of estrogen.) Lipschutz' 1950 book on steroid hormones and tumors summarizes his work.
>
> Contemporaries of Loeb and Lipschutz, Joseph Needham, C.H. Waddington and J.W. Orr, argued that cancer evolves through a series of developments in the tissues, rather than in single cells.
>
> A few years later, Hans Selye showed that the partial isolation of tissue itself (for example, growing inside a small glass tube implanted in a rat) caused a tremendous acceleration of the aging process in the isolated cells and matrix. An impermeable sheet of plastic implanted in an animal tends to cause a cancer to develop, if it is folded to form a concavity. The thickened connective tissue matrix that develops with aging, irritation, and stress creates innumerable areas in which cells are similarly cut off from full contact with their normal environment.
>
> Estrogen treatment at menopause produces alkalosis and hyperventilation. Alkalosis stimulates peroxidation and various other harmful stress-products. Prenatally, if estrogen excess doesn't kill the fetus, it retards its brain growth, because many of its metabolic actions are powerfully antigestational--actions that are used medically in the contraceptive pills and abortion pills.
>
> All cancer cells produce lactate even in the presence of oxygen, and this increases their intracellular alkalinity, promoting swelling, calcium uptake, and proliferation. Continued exposure to lactic acid increases collagen formation and fibrosis.

### Source 10 — Vitamin D may prevent (and even reverse) uterine fibroids

Georgi Dinkov · Article · Nov 16, 2022 · https://haidut.me/?p=2058

> Yet another big win for vitamin D, much to the chagrin of the medical establishment, which has been throwing “mud” (read: fake, ghostwritten studies) against vitamin D ever since it showed so much promise in human studies for both preventing and treating COVID-19. Now, the study below demonstrates yet another serious condition where vitamin D may be able to both “prevent and treat”. Namely, the dreaded uterine fibroids, which affect 80%+ of women at least once in their lifetime, and the rates of which continue to increase. In other words, a disease that affects virtually all women, and for which the only available “treatments” are surgery and/or even radiation. Some doctors prescribe synthetic progestins, but those have demonstrated an unacceptable level of side effects, too high for even medicine’s increased tolerance for homicidal interventions. As such, the synthetic progestins are not widely used as treatment. On top of that, those treatments are not only dangerous, but they do not resolve the condition as the fibroids invariably reoccur after a few years. What’s worse, these fibroids have a high chance of turning into uterine/endometrial cancer, so an effective prevention/treatment would be a huge win for public health. Well, based on the study below, it looks like humble vitamin D may be able to fit the bill. Keeping its blood levels above 20ng/mL may have a significant preventive effects and a level above 30ng/mL may even shrink/remove the fibroids. Btw, since I mentioned the synthetic progestins and it is accepted that progestins have beneficial effects, using bioidentical progesterone may be another viable treatment option but without the side effect risks of synthetic progestins. Finally, multiple studies have demonstrated synergism between vitamin D and bioidentical progesterone, allowing for much lower doses of each to be used when taken together. So, a combo of low-dose vitamin D and bioidentical progesterone may very well be the “killer combo” mainstream medicine has been looking for and dares not discuss in public out of fear the sales of surgeries, radiation treatments and synthetic progestins will collapse for good.
>
> [references]

_Generated 2026-07-20 from the Bioenergetic Oracle corpus._