Fasting and Cancer: All You Need To Know

Cancer, the big C, the word we all dread hearing after our medical check-ups.

The high prevalence of certain types of cancer—breast cancer for women, prostate cancer for men, and colon and skin cancer for both sexes—can be a cause for worry. Thankfully, Mother Nature has provided foods to help decrease cancer risk.

There are certain healthy foods that can fight cancer: antioxidant-rich green tea, blueberries, oranges, cruciferous veggies, organic meats, and the list goes on. By cutting chemical-laden, artificial foods from our diet, we can lower risk of cancer (and other diseases, everything from insulin resistance and diabetes to cardiovascular disease) even further.

But what if “how” you eat is as important as “what” you eat? What if there was a diet that could help to strengthen your body’s defenses against cancer so it could fight off carcinogens and tumors all on its own?

This article examines how a fasting or fasting-like diet can help in the fight against cancer.

We’ll look at the science behind fasting and cancer, how fasting makes chemotherapy more effective, and how it recruits your immune system to get involved, too.

We’ll also dive into the possible risks and hazards of fasting and show you how to safely and effectively reduce calorie intake to maximize your body’s defense and repair mechanisms.

Introduction: Can Fasting Help Fight Cancer?

For years now, scientists have known that fasting triggers important repair and restorative mechanisms in the human body.

You see, fasting activates an internal process called autophagy. Autophagy is how the human body reuses old and damaged cellular parts [1] to produce new cells. Think of it as your body’s recycling system: it allows your cells to disassemble any components that are “junk” or non-functioning, then reform and reassemble them into new, functional cell components.

Fasting and calorie-restriction diets are known to trigger autophagy. Effectively, limiting the amount of calories you consume signals to your body that it has to make use of what cellular material and energy it already has, because no more is coming (for the duration of the fast). Autophagy is our body’s way of remaining fully functioning even in periods with very little caloric or nutrient intake. It’s the survival mechanism that kept the human race alive during periods of food scarcity or even starvation.

Knowing what the body is capable of, what autophagy can do, scientists have attempted to determine whether it could be used to disassemble cells damaged by cancer and reassemble them into new, normal cells that are cancer-free.

Multiple studies suggest that fasting can aid in the fight against cancer.

Let’s dive in…

The Science Behind Fasting and Cancer

In 2016, the University of Southern California published an article that detailed the results of two different studies into the effects of fasting on cancer. Both studies were conducted within the University, and the results were fascinating.

Previous research had indicated that “a short-term fast (caloric restriction) starves cancer cells and facilitates chemo drug therapies to better target the cancer.”

In another prior study, researchers had found that fasting-like diets could help to slow the progression of multiple sclerosis, as it led to the death of unhealthy cells and the production of new, healthy cells. (Autophagy hard at work once again!)

How Fasting Enhances Chemotherapy Effectiveness and Activates the Immune System

In the USC studies, mice were placed on a low-calorie, fasting-like diet, which was given along with chemotherapy to treat the cancer. The mice were being treated for breast and skin cancer, and it was discovered that the fasting-like diet worked with the chemotherapy to “activate the immune system and expose the cancer cells to the immune system”.

Basically, the low-calorie fasting diet helped the body to be more effective at dealing with the cancer on its own.

However, it wasn’t just the body’s internal defenses that were boosted. According to the lead researcher, the diet and chemo combo “made a wide range of cancer cells more vulnerable to an attack by the immune cells while also making the cancer more sensitive to the chemotherapy.”

Basically, the T-regulatory cells in the body were expelled thanks to the fasting diet. These cells actually protect cancer cells, thanks to the increased production of the enzyme hemo oxygenase (HO-1) that resulted from the presence of tumors. This enzyme tricks your immune system into thinking that the cancer cells shouldn’t be killed, so our bodies are unable to eliminate the good cells. But, as a result of the fasting diet, these T-regulatory cells were eliminated, so the mice’s bodies were able to get rid of the bad cancer cells on their own. When the chemotherapy was added, the cancer cells were vulnerable and thus more easily eliminated.

This discovery builds on the facts gathered from previous studies, which found that fasting diets helped to make chemo more effective at dealing with cancer cells. A second study published by USC found that a 3-day fasting-like diet was “safe and feasible” for the 18 mice patients undergoing chemotherapy.

When the mice were put on four days of the fasting-like diet with chemotherapy treatments added, the tumor growth was slowed without damaging the normal, healthy cells in the body. This worked on both breast and skin cancers! Another study found that three cycles of the fasting-diet-and-chemo combo led to a 33% increase of white blood cells, which are responsible for fighting cancer cells. There were also TWICE the number of progenitor cells in the blood marrow, and the cancer-killing cells in the immune system were more effective at decreasing tumor size.

Research Insights: Fasting for Tumor Reduction

Why does cutting back on food intake help to increase immune response? According to the head researcher, “It may be that by always being exposed to so much food, we are no longer taking advantage of natural protective systems which allow the body to kill cancer cells. But by undergoing prolonged fasting or a fasting-mimicking diet, you are able to let the body use sophisticated mechanisms able to identify and destroy the bad but not good cells in a natural way.”

What’s amazing is that fasting can work on a variety of tumor cells and cancer types. One 2022 review of multiple medical studies [2] found that fasting has the potential to be effective against:

• Breast cancer
• Head and neck cancer
• Prostate cancer
• Colon cancer
• Lymphomas
• Ovarian cancer
• Melanoma
• Lung cancer

and others…

Pairing it with other cancer treatments—including radiation and chemotherapy—can not only make the body potentially more effective at fighting the cancer, but decrease the damage done to the body by these cancer treatments and speed up recovery time.

Thanks to all this research, fasting diets may soon become more common recommendations for those trying to fight cancer, possibly even for cancer prevention to stop tumor development in its tracks.

Water-only fasting and chemo has proven safe for humans, and 72-hour fasting diets can lead to reduced side effects from cancer treatments. With physician monitoring, fasting and chemo may soon be a highly effective method to treat cancer and speed up the healing process!

Safety of Fasting for Cancer Patients

It’s important to understand that fasting does come with its own inherent safety risks.

You are effectively depriving your body of crucial nutrients, as well as the energy it requires to function. There is a risk of poor metabolic health, or a decreased ability to produce and utilize energy once you return to normal eating patterns.

Experts at the NIH [3] have stated that fasting does come with potential side effects. For example, time restricted feeding for long fasting periods (16 to 18 hours per day) can lead to a higher rate of gallstones, which may require surgery to remove.

Harvard Medical School published a paper [4] listing a few possible side effects of fasting, including:

• Feelings of weakness, lethargy, or crankiness;
• Constipation or diarrhea;
• An urge to overeat (particularly common with intermittent fasting);
• Excessive weight loss (particularly among older adults), which can be a problem for those who already struggling to maintain healthy weight due to cancer treatments;
• Dangerous interactions with certain medications.

It’s imperative that you consult with your doctor or healthcare professional before undergoing any fasting or fasting-like diet.

How to Safely Integrate Fasting Into Your Life

If your healthcare provider or a medical professional has approved a fasting or fasting mimicking diet as a means of treating cancer (or addressing other health issues resulting from cancer or cancer treatments), here are some ways that you can safely go about fasting:

• Maximize hydration. Aim to drink at least 4-5 liters of water every day, particularly during the hours that you’re fasting. Your body typically obtains fluids from the food you eat, and without them, you’re at risk of dehydration if you don’t consume a lot of extra fluid. Drink plenty of water, tea, and black coffee to maintain a healthy fluid balance.

• Consider intermittent fasting. Intermittent fasting involves eating nothing (fasting) for 12 to 18 hours a day, then eating all of your calories in the remaining window (6 to 12 hours). This is a way to safely fast every day or on alternate days. Experts deem a 12 on/12 off fasting pattern “likely safe for most people” [5].

• Cut back on calories two days a week. Instead of diving deep into fasting and drastically restricting caloric intake, try just scaling back significantly but not excessively a couple of days per week. For example, if your normal dietary regimens call for around 2000, try cutting back to 1100 or 1200 during your fasting cycles. It mimics the effects of fasting and can trigger autophagy, but will be less likely to trigger the negative repercussions of a full-on fast.

• Make healthy food choices. This is the most important part of smart fasting. Make sure you’re eating food that is high-quality and natural, with a good balance between lean proteins, carbohydrates and whole grains, and healthy fats. The foods you choose to eat during your dietary restriction should also be rich in vitamins, minerals, fiber, and antioxidants, all of which are needed to meet your body’s daily nutritional needs.

• Be active. Physical activity during periods of caloric restriction can have positive metabolic effects, maintain healthy hormone levels, facilitate energy production, and aid in digestion. Stick with light activity that won’t tax your body excessively, but make sure to move: walk, run, cycle, row, etc.

Be smart and safe in your fasting, and you can give your body a fighting chance against cancer without impairing its function or triggering other health problems.

Future Potential: Integrating Fasting into Cancer Treatment

Research [6] is constantly finding more ways that fasting can be used to improve cancer—from triggering autophagy that scavenges cellular junk to enhancing chemotherapy to boosting the immune system.

Every year, more clinical trials are assessing the health benefits of fasting or fasting-like diets on cancer, and trying to find new, safe, and healthy ways to harness the power of autophagy and the body’s internal defense and restoration mechanisms for the fight.

Further research is needed to find conclusive evidence to indicate the best path forward, but for now, it’s encouraging to know that fasting is being viewed as a potential cancer treatment—or, at the very least, one more tool in a doctor’s medicine bag to help you get and stay healthy.

Conclusion: Harnessing Nature to Fight Cancer

Consider fasting or fasting-like diets as a health-booster and an aid in the fight against cancer. A few small changes to the way you eat—now just the what, but the how—can make a huge difference in your body. You can see a more effective immune defense and greater cellular repair, which results in a stronger, more resilient body.

As you’ve seen, harnessing natural mechanisms like autophagy can be a powerful way to support your body in healing, protecting itself, and staying resilient in the face of disease. If you’re looking for a way to reinforce this process every day, even outside of fasting windows, supplementation can play a key role.

Restore Life contains science-backed ingredients to make you look and feel younger. Plus, it also has some exceptional benefits for your skin, blood sugar, bones, heart, joints and cellular health. 

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Click here to learn more about Restore Life and find out how it can change your future for the better by helping your body regenerate, improving autophagy, and allowing you to live your best, youngest, and healthiest life!

Frequently Asked Questions

What is the biggest contributor to cancer?

While there are a great many risk factors for cancer—including age, alcohol consumption, diet, sunlight, infectious agents, and even obesity (high body composition)—the American Cancer Society believes that cigarette smoking is the biggest contributor [7]. Smoking was linked to almost 19% of all cancer cases, and almost 29% of all cancer deaths. By comparison, the next biggest contributor to cancer was excess body weight, but linked to only 7.8% of cancer cases and only 6.5% of all cancer deaths.

What feeds cancer the most?

Cancer cells need glucose, which is derived from sugar and carbohydrates, in order to grow. This is why the belief that “sugar feeds cancer” (high glucose levels contributes to the formation of tumors) has become so prevalent. But red meat and processed meats have a strong link to colorectal cancer, while alcohol has a strong link to multiple cancer types (including stomach, liver, pancreas, and even breast cancer) [8].

Which cancer has the worst survival rate?

Esophageal cancer has the worst survival rate, with just a 48.8% probability [9]. Close behind are pancreatic cancer (44.3%), liver cancer (37.3%), intrahepatic bile cancer (also 37.3%), and brain cancer (36%). The cancers with the highest survival rates are thyroid (99.9%), melanoma (99.6%), and breast cancer (99.3%).

Resources:

Effect of fasting on cancer: A narrative review of scientific evidence

Researchers Look to Fasting as a Next Step in Cancer Treatment

Cancer and Fasting / Calorie Restriction