With studies indicating that the consumption of red meat, such as pork and beef, elevates the likelihood of developing colon, breast, and other cancers, certain individuals diagnosed with cancer believe it's necessary to discontinue their intake of red meat—and indeed, they do. However, the efficacy of this practice in cancer treatment has been questioned, as stated by a clinical nutritionist.

"Red meat serves as a highly significant and notably efficient protein source essential for the restoration of regular cells impaired by chemotherapy, radiation therapy, or surgical procedures," remarked Kim Bo-eun, a clinical nutritionist affiliated with Samsung Medical Center, during an appearance on the Korea Blood Disease & Cancer Associations’ YouTube channel. She emphasized that, in her view, cancer patients ought to include red meat in their diet, notwithstanding certain research indicating an elevated potential for cancer recurrence and chronic ailments.

Kim elaborated that certain claims associating the excessive consumption of specific proteins with conditions like diabetes, cardiovascular disease, cancer, and mortality often lack substantial supporting evidence. Furthermore, she highlighted that red meat stands as a premium protein choice, characterized by an exceptional amino acid composition and heightened digestibility when contrasted with plant-based alternatives. Additionally, she emphasized that red meat represents a valuable reservoir of complete protein, encompassing an ample supply of essential amino acids.

"Anemia is a frequently observed condition during cancer treatment, and red meat demonstrates a rapid and effective influence on promoting anemia recovery while also aiding in its prevention," Kim said.

Protein is a major component of human tissue and plays a critical role in the production of many of the body's hormones and antibodies, which can be compromised by poor nutrition during cancer treatment.

"Protein is the preferred source of energy in the body when the energy supply is low, so it can only fulfill its role if there is sufficient energy supply," Kim added.

Protein deficiency can pose significant dangers for cancer patients. 

Insufficient protein intake can lead to decreased immunity, muscle loss, and metabolic dysregulation, according to Kim.

"In addition, low protein intake in the presence of chronic illness, trauma, or inactivity can lead to more rapid sarcopenia, which can lead to disability and even death."

How much red meat is adequate for cancer patients?

So, how much red meat should cancer patients consume, and in what manner? The World Cancer Research Foundation suggests a weekly intake of 300 to 500 grams of meat. For a single meal, the recommended portion of red meat falls between 60 to 120 grams, roughly equivalent to a slightly less than standard serving size.

In terms of preparation, it's advised to cook red meat through methods such as boiling, stewing, or sautéing. If grilling is preferred, it's recommended to opt for a light grilling technique to prevent charring. Incorporating red meat as a side dish three to four times a week is considered a balanced approach.

Cancer treatment and recovery from treatment as well as metabolic stress and exposure to environmental factors such as infection and immune response increase protein requirements, Kim said.

In some cases, it can be as much as twice as much as normal. 

"Prolonged cooking at high temperatures (200-250 degrees), such as over an open flame or in deep fryers, can produce heterocyclic amines (carcinogens), and the addition of nitrites, which are used as colorants in ham and sausage, can produce carcinogens such as N-nitroso compounds," she said. 

"It's important to eat as little processed meat as possible, and when you do eat meat, eat it with vegetables to prevent the absorption of carcinogens."

If a patient has trouble getting enough protein, he or she can take advantage of powdered protein supplements. 

However, it's important to note that there is currently no safe evidence for overdosing on protein supplements. 

In addition, the average cancer patient may be deficient in other nutrients when they are deficient in protein.

This is why patients shouldn't rely solely on protein powder for their protein needs if their overall nutrition is inadequate due to treatment side effects such as loss of appetite, nausea, and vomiting.

"During the course of treatment, patients are often eating fewer meals and snacks and are often deficient in both macronutrients and micronutrients other than protein," Kim said.

She recommended utilizing commercially available specialty foods that contain a combination of carbohydrates, protein, fat, and other micronutrients. 

One 200-milliliter serving of specialty food is equivalent to eating one-third of a serving of rice, one serving of fish, and one serving of greens (200 calories of energy and 9 grams of protein).

It's recommended that cancer patients consume 700 to 800 calories per meal for men and 500 to 600 calories per meal for women, so a can or packet of specialty foods can be helpful when meals are a little short. 

What if cancer patients are too sick to eat?

However, if patients have a severe canker sore, nausea, or vomiting during chemotherapy that makes it difficult to pass anything by mouth and they need to rely on specialty foods for entire meals, they may need to eat a little more than one can or packet per meal.

It's also not recommended that cancer patients follow a protein deficiency diet. "Indiscriminate intake of excessive amounts of individual amino acids in supplement form can lead to competition for absorption, amino acid imbalance, and increased risk of toxicity," Kim said. She cautioned that excessive nitrogen metabolism can lead to osteoporosis, and in people with reduced renal function, it can put a lot of strain on the kidneys.

Even if cancer patients are vegetarians, they need to eat animal proteins like eggs and milk. 

“While plant-based proteins are as effective as their animal-based counterparts, incorporating items like eggs or milk into one's diet enhances protein utilization considerably, beyond relying solely on pure plant-based sources,” Kim noted.

Meals for people with cancer should include unmilled grains, colorful vegetables and fruits, and a variety of protein sources such as fish, beans, and tofu, with fewer simple sugars and processed meats. 

Additionally, fruit and dairy products, such as milk, should be consumed once or twice a day as a snack to ensure you're getting enough protein. 

Additionally, it's vital to note that protein is optimally utilized when consumed in smaller portions during each meal, rather than in substantial quantities at once.

"It is possible to consume a full serving of protein at one time, but it is more efficient to utilize protein in small portions at each meal," Kim said. "It is recommended that cancer patients eat a healthy balanced diet that includes adequate protein and avoid fast food and other processed foods that are rich in fat and sugar."