Scientists have discovered that obesity limits the body’s natural anti-cancer systems. While the association between obesity and cancer has been well-documented, the mechanisms by which obesity inhibits the immune system have only recently begun to be understood.
In a groundbreaking study, researchers have shown that fat cells prevent natural killer (NK) cells and other immune cells from destroying cancer.
More than a third of the world’s population is overweight or obese, contributing to diabetes, heart disease, and cancer. In fact, nearly half of certain cancers are thought to be due to obesity. And despite a deluge of public health efforts, the problem only seems to be getting worse.
While many health risks associated with being overweight are well understood, one risk is not: immune surveillance.
What Is Immune Surveillance?
The concept of immune surveillance is relatively straightforward. The immune system is our best defense against disease and plays an important role in combating cancer. But tumor cells can escape immune surveillance by mutating and disguising themselves as other cells. That’s where natural killer cells come in.
Natural killer (NK) cells are white blood cells found in our lymphatic system. These cells are uniquely designed to hunt cancerous cells and destroy them, hence the name “natural killer.” In the immune system, these cells are our first and best defense against cancer. Healthy NK cells are absolutely vital in your body’s battle with disease.
The Connection Between Obesity and Cancer
Unfortunately, research has found that obesity inhibits NK cells’ ability to destroy cancerous or precancerous cells. While NK cells can still find tumors, fat cells block the mechanisms that destroy cancer cells. This is referred to as “metabolic paralysis” and renders NK cells virtually useless in the fight against cancer.
The mechanism is now well understood. Obesity induces robust PPAR-driven lipid accumulation in NK cells, causing complete paralysis of their cellular metabolism and trafficking. Fatty acids clog up the cytotoxic machinery, preventing it from reaching the NK cell-tumor synapse.
Professor Lydia Lynch, a professor of immunology and the lead researcher on the study, believes the damage to NK cells can be reversed.
Despite increased public awareness, the prevalence of obesity and related diseases continue. Therefore, there is increased urgency to understand the pathways whereby obesity causes cancer and leads to other diseases, and to develop new strategies to prevent their progression.
Our results highlight immuno-metabolic pathways as a promising target to reverse immune defects in obesity and suggest that metabolic reprogramming of Natural Killer cells may kick-start their anti-cancer activity and improve treatment outcomes.”
The Good News: The Damage Is Reversible
The good news is that obesity-related immune damage can be reversed. Metabolic paralysis can be overcome by kick-starting natural killer cells’ metabolic function. Professor Lynch even theorizes that the damage to NK cells may also explain the increased risk of infection in obese patients. If that’s true, restoring these cells’ metabolic function may have even greater effects.
Recent research confirms this. A 2025 study showed that switching from a high-fat diet to a normal diet led to weight loss and restored NK cell function. Mitochondrial mass and ATP content became comparable to lean subjects, and NK cells fully regained their cytotoxic capabilities.
How Obesity Fuels Cancer: The Full Picture
The link between obesity and cancer is undeniable, and the mechanisms extend far beyond NK cell paralysis.
Chronic Inflammation: Excess fat tissue triggers a stress response that alarms the immune system, creating chronic inflammation throughout the body. This inflammation reprograms immune cells so they no longer combat cancer cells but rather aid their survival and support tumor growth.
Hormonal Changes: Obesity causes long-lasting inflammation and higher-than-normal levels of insulin, insulin-like growth factor, and sex hormones. These changes may lead to cancer. The risk of cancer increases with the more excess weight a person gains and the longer a person is overweight.
Adipose Tissue Distribution Matters: A 2025 Mendelian randomization study found that where fat is stored matters greatly. Higher abdominal subcutaneous adipose tissue increased the risks of endometrial cancer, liver cancer, and esophageal adenocarcinoma. Higher visceral adipose tissue and liver fat increased liver cancer risk.
The Numbers Are Staggering: According to the CDC, being overweight or having obesity is associated with a higher risk of getting 13 types of cancer. These cancers make up 40% of all cancers diagnosed in the United States each year. More than 716,000 obesity-associated cancers occurred in the United States in 2022, including more than 220,000 among men and 495,000 among women.
What the Research Means for You
The sad news is that all of these problems are preventable. Shutting down our natural immune systems is just one of the ways that obesity increases our risk for cancer and other diseases. It also leads to inflammation, diabetes, heart disease, and other health risks that extend beyond cancer.
But the research is also clear: the damage is reversible.
Weight loss through dietary change and physical activity improves NK cell function. In fact, one study found that NK cell activity was suppressed in women who lost weight through diet alone, but was preserved in those who combined diet with exercise. This underscores that both diet AND movement matter.
Several ways can help keep your natural killer cells healthy, abundant, and strong. When it comes to obesity and cancer, it all starts with your diet. In fact, more than half of the immune system is located in the gut. A healthy gut promotes nutrient absorption, prevents weight gain and obesity, and protects against autoimmune disease and cancer.
The link between obesity and cancer is undeniable. In today’s world, the standard American diet consists of sugars, carbs, processed meats, and dangerous synthetic fats. Our food is being pumped with hormones, soaked in poison, or both. But your body is a temple, and you can protect yourself from diseases like cancer. With the right nutrition and an active lifestyle, you can live a long, happy, and healthy life.
So what diet is best? I’m impressed with the plant-based diet Engine 2.
Ty i loook forward to receiving your emails You are truly blessed ! Annette
Hi Annette,
Thanks for being part of our mission! We hope you learn lots from our emails, articles, and videos. Best wishes!
Hello, I am very upset to find that obesity can lead to cancer. To tell you the truth, I was a slim size 10 until my body gave a big heave of despair and released all kinds of heavy metals and aspartame (from before anyone knew it was a problem) into my upper body. That was Feb. 22, 2002, the day in my life that will live on in infamy…when I turned purple from the chest up for 10 days. No doctor knew what to do for me, and I also became allergic to the world overnight and needed new glasses and thyroid medicine for the first time ever. Since then, my body has slowly continued to pile on fat around my middle section, even though I barely eat anything that is not organic, gluten free, and rarely anything that contains any sugars besides low glycemic coconut sugar and sweetleaf stevia. SO PLEASE stop telling me it’s my diet and lifestyle that is making me continue to gain fat and have a fatty liver!!! NO, IT IS NOT!!! All I can think of is that my NAFLD is a result of chromium deficiency and choline deficiency. I work on this EVERY DAY, yet my latest (yesterday) Oligoscan for metals and minerals STILL shows my Chromium as nearly non-existent in my tissues! So, if I get cancer and die, I get cancer and die. There is only so much a person can do to fix a screwed up metabolism!!! I have worked SO HARD to fix and heal these issues through natural medicines, supplements, clean foods, prayer and superfoods, including 7 sacred mushroom mix. So has it all made any difference yet? Well, in 3 mos. there is a noticeable improvement in my already O.K. immune system (yesterday’s Oligoscan), but my body’s chromium level is still considered non-existent! WHAT ELSE? WHAT NOW??? NO IT IS NOT MY DIET AND LIFESTYLE!! I even have done many heavy metal detoxes, but they ALL only make me much more ill, even the Cytodetox product from Dr. Dan Pompa. All of this, even if I take loads of Activated Charcol, Magnesium, Liver Efficiency caps. and Minrex Minerals to assist my liver in the process. HELP!!
Joyce,
I am so sorry to hear your story, it must be terribly frustrating. You are doing the right thing taking charge of your own health. Never give up on the hope to find answers. I just finished a book by Anthony Jay, PhD. He is a PhD chemist, Mayo Clinic recently hired him for research in stem cell therapy. You can watch his YouTube videos, start with his video on Fluoride. After watching his videos buy his book! I think he may be the smartest scientist to date on health.
The sooner we wake up to Big Food lobbyists, Big Ag (Monsanto) and Big Pharma tactics, we may start to heal our bodies. Pesticides in all of our foods, Round Up(glyphosate), Atrozine, and more.
I wish you the best on your quest for wellness. Never give up.
I feel your pain and posted my own story! I can only do so much and it’s in God’s hands. He knows how I will die which is 100% for sure. God doesn’t need our bodies he needs our hearts and souls. It’s so hard to be know we trusted and now we have to untrust people and put our trust in
God to guide us. I will pray for you.
Just wondering if all of this happened after a vaccine?
Hi
That was great.
Just wondered if having your tonsils out impacts immunity and if so how can I help balance this back
Hi Ty great article as always lots of good information I am fighting stage 4 colon cancer. God Bless You And Your Family
Do you have a recipe book I could buy and healthy diet to help avoid cancer please
Hi Enid,
We have lots of great recipes on our website. Here is a link: https://thetruthaboutcancer.com/?s=recipe
Joyce Stotts, my heart goes out to you…….there are SOOOOOOOOO many of us out there who can relate to EXACTLY what you are saying. I was really hopeful that Ty would have some kind of new breakthrough for obesity in the article:(. May God bring a breakthrough for those of us who struggle so much!!
Seems deuterium is the cancer trigger:
AS we progress with more knowledge on deuterium, we find that sugar triggers insulin and that makes the sugar make huge fat cells. Nature tends to favor more deuterium in sugar and that sugar/deuterium can be expected to load up these fat cells with deuterium.
Then the largest cancer info associates fat tissue with impaired NK and other immune cells. Mitochondria energy impairment is also well associated with cancer etiology.
Thus, it appears the making of cancer is well involved with too much deuterium fat stores associated with too much sugar diet forming insulin spikes that make the high deuterium loaded fat cells and the locations then stall the NK cells as the attempt to fix problems.
AS we progress with more knowledge on deuterium, we find that sugar triggers insulin and that makes the sugar make huge fat cells. Nature tends to favor more deuterium in sugar and that sugar/deuterium can be expected to load up these fat cells with deuterium.
Then the largest cancer info associates fat tissue with impaired NK and other immune cells. Mitochondria energy impairment is also well associated with cancer etiology.
Thus, it appears the making of cancer is well involved with too much deuterium fat stores associated with too much sugar diet forming insulin spikes that make the high deuterium loaded fat cells and the locations then stall the NK cells as they attempt to fix problems.
Let us see how long TTAC can deny the obvious
The fat globing the NK cells sets off more correlation with fat issue and that with Sugar and deuterium.
High LDL and triglyceride makes arterial plaque.. Low-density lipoprotein is the carrier of bad cholesterol—which is likely loaded with deuterium. cell walls are made of lipids and too much deuterium makes the cells very sticky.
Get on into diabetes and the fat is seen to make fatty liver and bind up cells with fat that sets up insulin resistance. The only way to limit this is eat very low sugar so the insulin will not spike and store high deuterium fats made from Sugar overloads.
Cell walls are made of lipids (fats) and nerve sheaths are myelin and a lipid fat. So, the correlations are tracking back to fats causing the problems and then one should well consider the additional deuterium and its bonding strengths due to deuterium.
So, now it shows links to cancer via NK fat issue, to diabetes showing similar fat issues, and then on into nerve disorders.
The fixes are things like MCT oils and Omega-3 oils, dump the white fat, eat low carbs/sugar. Eat meats connected with low deuterium grass feed, and low deuterium butters from grass fed cows. They add in fasting to burn off the sugars and excess deuterium loaded fats. Then drink low deuterium water to lower the body retention of deuterium and make fats that are low in deuterium.
The hypothesis of deuterium moves into reality.
Add in the molecular hydrogen effect and that runs the ATP nano-motors with less deuterium than that from sugar metabolism.
But the corrupted food supplies and bad doctor knowledge is set to depopulate the Earth.
Does anyone KNOW how the body metabolizes Stevia and/or the natural fruit sugars? Do these negatively affect and lower the body’s immunity? If so, to what degree? Are complex carbs handled by the body differently than carbs in general. Should all of these be omitted from a body that is fighting cancer.
This just makes me cry! I’ve tried to loose weight for ever! I lost 50 pounds 3 years ago after being shed on by Covid jabs that’s a story in itself. Yet my whole life has been an issue with loosing weight. I eat 1 teaspoon of maple syrup in my 1 cup of coffee with collagen every morning. Lots of grass feed, organic meats, vegetables and almost no carbs except red potatoes occasionally. How is it my grandmothers where over weight and did not have cancer, Amish grandmothers in studies show no cancer but overweight. I read just the opposite in other studies from this study. We trust the cdc, we trust studies run by big pharmaceutical and big food? It just puts more people on drugs. That’s how they make money. I am mobility limited due to doctors and over medicated by doctors 11 years ago! Thyroid! I still peddle 40 minutes a day. I have residual issues from al most dying from thyroid over medication.We are over medicating with statin, and metafornin. If you search history back on this stuff it’s crazy how we got to this point. I’m already anxious and trying so hard and now this? 😭😭😭😭😭😭😭😭😭