Hormone-dependent cancer: Foods that help and foods to avoid

Author: Sandra Krstev Barać, Master of Nutrition

Nutrition for hormone-dependent cancer

Our body uses hormones as messengers, or rather, to transmit information. They "rush" through the bloodstream to tissues and cells and influence numerous processes: growth and development, metabolism, sexual function, reproduction, mood, hunger... However, our hormones can sometimes work against us, for example when they help tumors grow and spread. In this case, we are talking about so-called hormone-dependent cancer, which means that tumor cells have receptors to which, like a key and lock, hormones can bind and stimulate the growth of malignant tissue.

Among hormone-dependent malignant diseases, breast, ovarian, uterine, prostate, and testicular cancers stand out. Of course, not all cases of the aforementioned diseases are sensitive to hormones, but statistics reveal that hormone-dependent tumors still prevail in prevalence. Estrogen, progesterone, and testosterone, or sex hormones, are the ones that stimulate the growth of these malignant tumors, but endogenous hormones are not the only problem. Exogenous substances with hormonal effects can also stimulate cell proliferation. Therefore, it is very important to know whether the cancer is hormone-dependent, so that we can apply the right therapy, but also so that we can help the healing process with our diet and lifestyle.

Basic nutritional recommendations

If you suffer from hormone-dependent cancer, your diet, if well-planned, can be your valuable ally. It is extremely important to eat well during and after therapy, because this will give you more strength and energy, contribute to a faster recovery and treatment outcome, make it easier to cope with the side effects of therapy, if they occur, and also maintain an adequate body weight, which is an extremely important item for cancer patients.

Regardless of the type of malignant disease, the diet of cancer patients should be varied and balanced, with a focus on whole plant foods. A variety of vegetables and fruits, as well as legumes and whole grains, and even herbs, are at the forefront here, as they are rich in numerous phytochemicals with strong anticarcinogenic effects, as well as fiber that can bind carcinogens. In addition, fiber can act as aromatase inhibitors, the enzyme that converts testosterone to estradiol, a property that is extremely useful in estrogen receptor-positive breast cancer.

In addition to this basic recommendation, it is also extremely important that:

• each meal contains a source of protein, of plant or animal origin

• fat intake is moderate, with an emphasis on healthy sources of fat such as olive and pumpkin oil, nuts, seeds

• at least 2 times a week, fish is on the plate as an excellent source of beneficial omega-3 fatty acids

• limit the intake of refined grains and flour or products made from them, as well as sugar-rich foods

• drink enough fluids, preferably water and herbal teas (especially green tea)

In practice, these recommendations translated onto the plate mean that half of the plate should be vegetables, a quarter should be quality sources of protein, and the remaining quarter should be starchy vegetables or whole grains. Use fats to prepare meals and as a condiment.

Should you eliminate soy and flaxseed from your diet?

You can read more about this topic in a separate article. When it comes to hormone-dependent cancers, especially those that grow under the influence of estrogen, such as breast cancer, some foods, such as soy and flaxseed, often cause concern among sufferers. The reason lies in the fact that they contain so-called phytoestrogens (isoflavones in soy and lignans in flaxseed), plant substances that have a similar structure and can act as weak estrogens and as such, in theory, can stimulate the growth of hormone-dependent malignant cells.

The thesis about phytoestrogens is full of controversy, but thanks to a series of studies conducted on humans, many experts emphasize that moderate soy intake is safe for everyone, including people who are currently undergoing therapy and those who have been cured, not only of breast cancer but of all malignant diseases sensitive to estrogen. Moderate intake specifically means consuming 1-2 servings of whole soy and minimally processed products per day, with one serving being:

• ½ cup cooked soybeans

• ½ cup cooked edamame beans

• 1 cup soy milk

• 1/3 cup tofu

The same goes for flaxseed. In fact, studies show that lignans from flaxseed have a positive effect on estrogen metabolism, in that they can stimulate the excretion of estrogen through feces and thus reduce its levels in the body. For a beneficial effect, the recommended amount is 2 tablespoons of ground flaxseed per day.

Although moderate intake of phytoestrogens through food is safe in hormone-positive malignant diseases, the same is not known for dietary supplements that contain them, so experts advise avoiding preparations with phytoestrogens altogether.

Foods to Limit

Red meat and dairy products are also on the list of controversial foods when it comes to hormone-dependent cancer. The link between saturated fat intake from meat and dairy products and the development of various types of malignant diseases is well established, and there is evidence that animal fats can increase the risk of estrogen- and progesterone-dependent breast cancer. However, when the disease occurs, it is not entirely clear whether these foods can be included in the diet. However, many experts advise that the intake of red meat and full-fat (but not low-fat) dairy products be eliminated or limited as much as possible.

The same applies to sugar and alcohol. Although sugar does not feed cancer as is often believed, frequent consumption of table sugar increases levels of insulin and insulin-like growth factor I (IGF-1), which can stimulate the growth of malignant tissue.

Alcohol, on the other hand, can increase estrogen levels in the body, and its excessive intake, regardless of the type, is known to increase the risk of breast cancer. However, there is not enough research on how moderate alcohol consumption affects the health of those already suffering from the disease. For now, it seems that alcohol intake (more than 3 drinks per week) increases the risk of relapse, but only in postmenopausal women, while the effect on younger women is insignificant. Despite this, experts agree that it is best to eliminate alcohol or at least limit it to special occasions only.

Brassicas are your ally

It is well known that consuming broccoli, cabbage, cauliflower, kale, and other brassicas reduces the risk of developing cancer, but it is wise to consume these valuable foods regularly even if you develop hormone-dependent cancer. Brassicas contain isothiocyanates and indole-3-carbinol, substances that stimulate the biotransformation of estrogen, as well as xenobiotics and carcinogens through the liver.

Additionally, brassicas also contain calcium-D glucarate, a compound that can inhibit beta-glucuronidase, an enzyme that contributes to the recirculation of estrogen in the body. Therefore, brassicas are an important ally in the fight against hormone-dependent cancer. It is advisable to consume these foods raw as much as possible and chew them well, because this way you can use more of these valuable anti-carcinogenic compounds.

Nutritional advice based on the type of therapy

Finally, considering the therapy you are receiving for your malignant disease, be sure to pay attention to some other details. For example, due to potential interactions, it is advisable to avoid grapefruit and grapefruit juice if you are on tamoxifen, a drug from the group of selective estrogen receptor modulators often used in the treatment of estrogen receptor-positive breast cancer.

On the other hand, if you are receiving adjuvant hormonal therapy with aromatase inhibitors (e.g. anastrozole or letrozole), keep in mind that these drugs negatively affect bone health and increase the risk of osteoporosis. Therefore, it is extremely important to consume foods rich in calcium, exercise moderately, and additionally take 1000 – 2000 IU of vitamin D daily through supplements.

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