Intermittent fasting has become a topic of great interest in oncology, especially in the last 10–15 years. It is not a treatment for cancer itself, but it can be a valuable adjunct alongside classic therapies and a healthy lifestyle. Its benefits are based on well-documented biological mechanisms, some of which have been confirmed in clinical and experimental studies.

Here are the main positive effects, explained in an easy-to-understand way:

1. Decrease in insulin levels and IGF-1 growth factor

• Insulin and IGF-1 (Insulin-like Growth Factor 1) are hormones that stimulate cell growth.
• Cancer cells divide rapidly and “take advantage” of an environment with high insulin and IGF-1.
• Through intermittent fasting, blood sugar decreases, insulin normalizes, and IGF-1 is reduced.
• This environment becomes less favorable for tumor proliferation, but supports normal cells, which adapt better to energy reduction.

• 🔹 Studies show that reducing IGF-1 can slow tumor growth and improve response to chemotherapy.

2. Activation of autophagy (“cellular cleaning”)

• Autophagy is the process by which cells “recycle” defective components, including damaged mitochondria or abnormal proteins.
• In cancer, autophagy is often blocked, and toxins accumulate.
• Intermittent fasting, especially after 16–24 hours, strongly activates autophagy.
• The result: normal cells become more resistant, while cancer cells become more vulnerable to treatments.

🔹 This mechanism is described as a “metabolic reset” effect, useful both in prevention and in supporting treatments.

3. Selective protection during chemotherapy (“Differential Stress Resistance”)

• During fasting, healthy cells enter a protective mode, reducing division and energy consumption.
• Cancer cells, however, cannot adapt to the lack of glucose and continue to divide chaotically, making them more sensitive to chemotherapy.
• This phenomenon was demonstrated in the studies of Valter Longo, who showed that a 48–72 hour fast before chemotherapy can:
  • reduce adverse effects on healthy cells,
  • increase the effectiveness of cytostatics.

4. Reduction of systemic inflammation

• Cancer is favored by chronic inflammation, and intermittent fasting reduces levels of:
  • CRP (C-reactive protein),
  • pro-inflammatory interleukins (IL-6, TNF-α),
  • oxidative stress.
• An environment with low inflammation is less conducive to tumor progression and improves immunity.

5. Improvement of antitumor immunity

• After fasting periods followed by healthy refeeding, the body produces new immune cells, including cytotoxic T lymphocytes that attack cancer cells.
• AHCC, which you are already using, can enhance the effect on immunity if integrated into a lifestyle with intermittent fasting.

6. Reduction of adipose tissue and estrogens in hormone-dependent cancers

• Adipose tissue is an important source of inflammation and hormones, including estrogens.
• In cancers such as breast or prostate cancer, reducing body fat decreases hormonal stimulation of the tumor.

🔹 In your personal experience, losing 18 kg through OMAD (One Meal A Day) contributed to metabolic regulation and maintaining an undetectable PSA.

7. Improvement of quality of life during treatment

• Many patients report:
  • less nausea during chemotherapy,
  • better energy,
  • more restful sleep,
  • increased mental clarity.
• These effects are associated with blood sugar stabilization and increased production of ketones, which become a clean fuel for the brain and muscles.

Important precautions

• It is not recommended in cases of cachexia (severe weight loss) or in very advanced cancers where the patient is already extremely weakened.