Tomato Sauce Put to the Test for Prostate Cancer

What happened when cancer patients were given three quarters of a cup of canned tomato sauce every day for three weeks?

“Occasionally…positive things happen in the field of cancer prevention science to popular, good-tasting foods.” Cruciferous vegetables like broccoli are wonderful, but they may be “a hard food for the public to swallow.” By contrast, who doesn’t like tomatoes?

As I’ve discussed previously, studies using high-dose supplements of lycopene, the antioxidant red pigment in tomatoes thought to be the active anti-cancer ingredient, failed over and over again to prevent or treat cancer. In fact, it may even end up promoting cancer, since lycopene may actually act as a pro-oxidant at the high levels one can get with supplements. But, lycopene in supplement form doesn’t appear to be effective at lower doses either. “There is a strong inverse [protective] correlation between the intake of fruit and vegetables and the incidence of certain cancers.” However, when we supplement with only a single compound isolated in pill form, we may upset the healthy, natural balance of antioxidants.

It does seem to be quite the human hubris to think we can reproduce the beneficial effects of consuming entire fruits and vegetables by giving supplements of a single phytochemical, which would normally interact with thousands of other compounds in the natural matrix Mother Nature intended. “In addition to lycopene, [other] known carotenoids in tomatoes and tomato-based products include β-carotene, γ-carotene, ζ-carotene, phytofluene, and phytoene, all of which…have been found to accumulate in human prostate tissue.” There are also numerous non-carotenoid compounds in tomatoes that may have anti-cancer activity, not to mention all of the compounds we have yet to even characterize.

It’s not about finding the one magic bullet, though. As one study title reads, “The anti-cancer effects of carotenoids and other phytonutrients resides in their combined activity.” For example, as you can see at 1:52 in my video Tomato Sauce vs. Prostate Cancer, at the low concentrations of the tomato compounds phytoene, phytofluene, and lycopene that are found in most people who eat normal amounts of tomatoes, there’s very little effect on cancer cell growth in vitro when used separately. But, when they are combined together, a non-effective dose of phytoene and phytofluene plus a non-effective dose of lycopene somehow become effective, significantly suppressing prostate cancer cell growth. The same synergy can be seen across foods. Curcumin, the yellow pigment in turmeric and curry powder, tomato extracts, and the vitamin E found in nuts and seeds do little individually to inhibit pro-growth signaling of prostate cancer cells—less than 10 percent—but all three together suppress growth signaling about 70 percent. The whole is greater than the sum of its parts.

So, instead of giving cancer patients lycopene pills, what if we give them some tomato sauce? Researchers gave 32 patients with localized prostate cancer three quarters of a cup of canned tomato sauce every day for three weeks before their scheduled radical prostatectomy. In their bloodstream, PSA levels dropped by 17.5 percent. PSA, prostate-specific antigen, is a protein produced by prostate gland cells, and elevated blood PSA levels are routinely used to monitor the success of cancer treatment. “It was surprising to find that the 3-week, tomato sauce-based dietary intervention” could decrease PSA concentrations in men with prostate cancer. As well, free radical damage of the DNA in their white blood cells dropped by 21 percent. Imagine how antioxidant-poor their diet must have been beforehand if less than one cup of tomato sauce a day could reduce DNA damage by more than a fifth! 

What did they find in their prostates, though? Human prostate tissue is thought to be “particularly vulnerable to oxidative DNA damage by free radicals, which are thought to play a critical role in all stages of carcinogenesis,” that is, of cancer formation. This may be for a number of reasons, including fewer DNA repair enzymes. Well, the researchers had tissue samples taken from biopsies before the tomato sauce regimen started, as well as tissue samples from surgeries after three weeks of tomato sauce, and resected tissues from tomato sauce-supplemented patients had 28 percent less free radical damage than expected. I show a graph of the DNA damage in the prostate before the tomato sauce and after just 20 days of sauce at 4:18 in my video. You can see the drop yourself. What’s interesting is there was no association between the level of lycopene in the prostate and the protective effects. Tomatoes contain a whole bunch of things, some of which may be even more powerful than lycopene.

Regardless, in contrast to the lycopene supplements alone, the whole food intervention seemed to help. To see if lycopene plays any role at all, one would have to test a lycopene-free tomato—in other words, a yellow tomato. So, what if you compared red tomatoes to yellow tomatoes, which have all the non-lycopene tomato compounds, to straight lycopene in a pill? Researchers fed people red tomato paste, yellow tomato paste, lycopene pills, or placebo pills, and then dripped their blood onto prostate cancer cells growing in a petri dish. As you can see at 5:18 in my video, the red tomato serum—the blood from those who ate red tomato paste—significantly decreased the prostate cancer cell’s expression of a growth-promoting gene called cyclin D1, compared to those not eating anything. This downregulation of the gene by the red tomato consumption “may contribute to lower prostate cancer risk by limiting cell proliferation.” The red tomato seemed to work better than the yellow tomato, so maybe the lycopene helped—but not in pill form. This gene “was not regulated” by the lycopene pill serum, indicating that it may be something else. And, lycopene alone significantly upregulated procarcinogenic genes. “Therefore, it can be stated that tomato consumption may be preferable to pure lycopene…”

So, what’s the best way? A spouse wrote to the editor of the Harvard Men’s Health Watch, saying their husband wants to have pizza for his prostate but they don’t think it’s a healthy food. The doctor replied with the suggestion of a “cheese-free pizza (with broccoli instead of pepperoni, please)” or just some “tomato juice.”

Why eat tomato sauce when you can just take lycopene supplements? See my video Lycopene Supplements vs. Prostate Cancer.

Are there any foods we should avoid? Check out, for example, Prostate Cancer Survival: The A/V Ratio and How Our Gut Bacteria Can Use Eggs to Accelerate Cancer.


We may be able to prevent cancer and even reverse the progression of cancer with diet. See: 

It isn’t always easy to get guys to change, though. See Changing a Man’s Diet After a Prostate Cancer Diagnosis.

In health, 

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Dr. Gundry’s The Plant Paradox Is Wrong

A book purported to expose “hidden dangers” in healthy foods doesn’t even pass the whiff test.

I started getting emails about The Plant Paradox, a book purporting to expose “the hidden dangers in ‘healthy’ foods that cause disease and weight gain”—foods like beans, whole grains, and tomatoes. Hidden dangers? The author’s talking about lectins in a rehashing of the discredited Blood Type Diet from decades ago. I reviewed it a while ago in my video Blood Type Diet Debunked, but it just keeps coming back. The Plant Paradox was written by an MD, but if you’ve seen my medical school videos including Physicians May Be Missing Their Most Important Tool, you’ll know that is effectively an anti-credential when it comes to writing diet books, basically advertising to the world that they’ve likely received little or no formal training in nutrition. Dr. Atkins was, after all, a cardiologist. Even when we give the benefit of the doubt, the problem is it doesn’t even seem to pass the sniff test, as I discuss in my video Dr. Gundry’s The Plant Paradox Is Wrong.

If lectins are bad, then beans would be the worst, so bean counters would presumably find that bean eaters cut their lives short. But, the exact opposite may be true, with legumes—beans, split peas, chickpeas, and lentils—found to be perhaps “the most important dietary predictor of survival in older people” in countries around the world. As Dan Buettner pointed out in his Blue Zones work, lectin-packed foods are the “cornerstones” of the diets of all the healthiest, longest-lived populations on the planet. Plant-based diets in general and legumes, the most lectin-lush of foods, in particular are a common thread among longevity Blue Zones around the world, as you can see at 1:30 in my video.

If lectins are bad, then whole-grain consumers should be riddled with disease when in fact “whole grain intake is associated with a reduced risk of coronary heart disease,” the number one killer of men and women, “cardiovascular disease, and total cancer, and mortality from all causes” put together. This means that people who eat whole grains tend to live longer and suffer from fewer “respiratory diseases, infectious diseases, diabetes, and all non-cardiovascular, non-cancer causes” to boot. And, this is not only the case in population studies. As I showed in my video Can Oatmeal Help Fatty Liver Disease?, you can randomize people into whole grain interventions and prove cause-and-effect benefits. It’s the same with tomatoes. When you randomize women to a cup and a half of tomato juice or water every day, all that nightshade tomato lectin “reduces systemic inflammation” or has waist-slimming effects, reducing cholesterol as well as inflammatory mediators.

So, when people told me about The Plant Paradox, I thought to myself: Let me guess. He sells a line of lectin-blocking supplements. And, what do you know? His Lectin Shield capsules “assist your body in the fight against lectins” for only $79.95 a month. That’s only about a thousand dollars a year—a bargain for “pleasant bathroom visits.” Then, of course, there are ten other supplements for sale, so for only $8,000 or $9,000 a year, you can lick those lectins. Let’s not forget his skincare line. “Firm + Sculpt” for an extra $120 a month, which is all so much more affordable when you subscribe to his VIP club.

Look, people ask me all the time to comment on a new blog, book, or YouTube video, and I remind them that a hundred thousand peer-reviewed scientific papers on nutrition are published in the medical literature every year and we can barely keep up with those. But because people continually emailed me about this book, I decided I’d give it a chance.  He tells us to “forget everything you thought you knew was true.” (Diet books love saying that.) Okay. Ready? Chapter 1, citation 1: “Eating shellfish and egg yolks dramatically reduces total cholesterol.” What?! Egg yolks reduce cholesterol? What is this citation? I’ve linked the paper he cites on shellfish consumption so you can see it for yourself. By now, you know how these studies go. How do you show a food decreases cholesterol? Remove so much meat, cheese, and eggs that, overall, saturated fat falls—in this case, about 50 percent, as you can see at 4:15 in my video. If you cut saturated fat in half, of course cholesterol levels are going to drop. So, the researchers got a drop in cholesterol after removing meat, cheese, and egg yolks, yet that’s the paper he uses to support his statement that “egg yolks dramatically reduce[d] cholesterol.” That’s unbelievable! That’s the opposite of the truth. As you can see at 4:36 in my video, the truth is if you add egg yolks to people’s diets, their cholesterol goes up. How dare he say otherwise? What’s more, it’s not like he’s spewing some harmless foolishness, like saying the Earth is flat. Heart disease is the number one killer of men and women. His claims could actually hurt people.

So much for my giving him the benefit of the doubt.

This is an unusual article for me. I normally try to stay out of the so-called diet wars and just stick to bringing you the latest science. Roughly 100,000 papers are published on nutrition in the peer-reviewed medical literature every year, and we have a hard enough time keeping up with them, but let me know what you think: Would you like me to allocate time to more of these types of reactive discussions?

You’ll note I never really addressed Dr. Gundry’s thesis about lectins, but I do exactly that in these two videos: How to Avoid Lectin Poisoning and Are Lectins in Food Good or Bad for You?.


Here are links to the videos I alluded to in this article, if you want to learn more:

What else can tomatoes do? See Inhibiting Platelet Activation with Tomato Seeds.

One of the key reasons whole grains may be so beneficial is their effect on our good bacteria. Check out Gut Microbiome: Strike It Rich with Whole Grains and Microbiome: We Are What They Eat to learn more.

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Dietary Cure for Hidradenitis Suppurativa

What is the role of dairy- and yeast-exclusion diets on arresting and reversing an inflammatory autoimmune disease?

A landmark study suggested that exposure to dietary yeast, like baker’s yeast, brewer’s yeast, and nutritional yeast, may worsen the course of Crohn’s disease, an autoimmune inflammatory bowel disease. The reason the researchers even thought to do the study was because Crohn’s patients tend to have elevated levels of antibodies to yeast, but Crohn’s is not the only autoimmune disease with increased yeast antibodies. The same has been found in lupus patients, found in rheumatoid arthritis, found in another joint disease called ankylosing spondylitis, found in autoimmune liver disease, and also found in autoimmune thyroid disease. So, might avoiding yeast help those conditions, too? They haven’t been put to the test, but hidradenitis suppurativa has. What is that? I discuss this in my video Dietary Cure for Hidradenitis Suppurativa.

Hidradenitis suppurativa can be a gruesome disease. It starts out with just pimples, typically along parts of the body where there are folds, such as the armpits, groins, buttocks, and under the breast. Then, painful nodules form that turn into abscesses and drain a thick, foul-smelling pus. And then? It gets even worse, forming active tunnels of pus inside your body.

And, it is not that rare. It has an estimated prevalence of about 1 to 4 percent, which is like 1 in 50. Clothes typically cover it up so it remains hidden, but you can often smell the pus oozing out of people. There are all sorts of surgical options and chemotherapy, but why did researchers even think to try diet for the condition? I mean, since Crohn’s is a disease of intestinal inflammation, you can see how a food you react to could make matters worse, but why a disease of armpit inflammation? Because there seems to be a link between hidradenitis suppurativa and Crohn’s disease. Having one may make you five times more likely to have the other, so there may be an “immunopathogenic link” between the two—they may share similar abnormal immune responses. Given that, if cutting yeast out of Crohn’s patients’ diets helps them, then maybe cutting it out of the diets of people with hidradenitis suppurativa might help them. A dozen patients with hidradenitis suppurativa were put on a diet that eliminated foods with yeast, like bread and beer, and they all got better, 12 out of 12. There was an “immediate stabilization of their clinical symptoms, and the skin lesions regressed,” that is, reversed, and went away within a year on the diet. Okay, but how do we know it was the yeast? By cutting out a food like pizza, you also may be cutting out a lot of dairy, and that also appears to help. Indeed, a dairy-free diet led to improvement in about five out of six patients.

See, those tunnels of pus are caused by the rupturing of the same kind of sebaceous glands that can cause regular acne. In hidradenitis suppurativa, however, they explode, and “[d]airy products contain 3 components that drive the process that blocks the duct [clogging your pores] and contributes to its leakage, rupture, and ultimate explosion.” First, there’s casein, which elevates IGF-1. (I have about a dozen videos on IGF-1.) Second, the whey and lactose, and third, the hormones in the milk itself—six hormones produced by the cow, her placenta, and mammary glands that end up in the milk. So, why not try cutting out dairy to see if things improve?

There is a whole series of nasty drugs you can use to try to beat back the inflammation, but as soon as you stop taking them, the disease can come roaring back. Even after extensive surgery, the disease comes back in 25 to 50 percent of cases, so we are desperate to research new treatment options. But, patients aren’t waiting. They’re getting together in online communities, sharing their trial and error though social media, and people have reported successes cutting out dairy and refined carbohydrates, like white flour and sugar. So, a dermatologist in New Hampshire decided to give dairy-free a try, and 83 percent of the hidradenitis suppurativa patients he tried it on started to get better. What’s more, he didn’t even try cutting the sugar and flour out of their diets. Now, he didn’t conduct a clinical trial or anything. He just figured why not give dairy-free a go? It’s not easy to conduct randomized, clinical, dietary interventions, but that doesn’t stop individual patients from giving things a try. I mean, you can understand why there have to be institutional review boards and the like when trying out new, risky drugs and surgeries, but if it’s just a matter of trying a switch from cow’s milk to soy milk, for example, why do they have to wait? “As patients search for an effective path to clearance [of this horrible disease], they need support and guidance to follow the most healthful diet available, free of dairy and highly processed sugar and flour. Nothing could be more natural.”

But what about the yeast? How do we know it was the yeast? In the study we discussed earlier, 8 of the 12 patients had just gone through surgery, so maybe that’s why they got so much better. It’s similar to when I hear that someone with cancer had gone through the conventional route of chemotherapy, surgery, and radiation before going to some questionable clinic and then attributes their cure to the wheatgrass colonics or whatever else they got. How do they know it wasn’t the chemo/surgery/radiation that saved them? Well, in this study, why do we suspect it was the yeast? Because not only did every single one of the patients get better, “all the patients demonstrated an immediate recurrence of skin lesions following accidental or voluntary consumption of beer or other foods” like bread. So, not only did the elimination of yeast result in “rapid stabilization” and “a slow, but complete, regression of the skin lesions within a year,” but, in every single case, within 24 to 48 hours of taking a little brewer’s yeast or other “yeast-containing foods,” BAM!—the symptoms were back. So, that’s why the researchers concluded a “simple exclusion diet could promote the resolution of the skin lesions involved in this disabling and [perhaps not so] rare disease.”

What was the response in the medical community to this remarkable, landmark study? “Why was there no mention of informed consent and ethics committee approval…?” Letter after letter to the editor of the journal complained that the researchers had violated the Declaration of Helsinki, which is like the Nuremburg Code or Geneva Convention to protect against involuntary human experimentation, and asked where was the institutional review board approval for this yeast-exclusion study? In response, the researchers simply replied that they had just told them to avoid a few foods. They had given them the choice: We can put you on drugs that can have side effects, such as liver problems, or you can try out this diet. “The patients preferred the diet.” Let’s not forget, I would add, that they were all cured!

Anyway, bottom line, by avoiding foods, like pizza, which contains both dairy and yeast, sufferers may be able to prevent the ravages of the disease.


This is the fourth and final installment of a video series on the role baker’s, brewer’s, and nutritional yeast may play in certain autoimmune diseases. If you missed any of the others, see:

For more on dairy hormones, see:

Check out our IGF-1 topic page if you’re unfamiliar with this cancer-promoting growth hormone, which I highlight in my video Animal Protein Compared to Cigarette Smoking.

In health,

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: