Every year, hundreds of the top cancer scientists from countries around the world converge to discuss the latest on diet and cancer. I’d like to share what I found to be the most interesting highlight from this year’s conference.

First, some background. One cancer cell never hurt anyone; two cancer cells never hurt anyone. But a billion cancer cells; that’s when we start getting into trouble. So, we have to slow and reverse the division and growth of cancer cells. We all have cells that could grow into tumors, but if we slow them down, our immune systems may be able to clean them up before they spell trouble.

Take breast cancer, for example—the most common cancer among American women. Like all cancers, it starts with one cell. This is a photomicrograph—a photograph taken under a microscope of an actual breast cancer cell, which then divides, and becomes two cells, and then four, eight, and so on. Every time the cells divide, the tiny tumor doubles in size. The tumor need double only about 30 times, and we’re up to a billion cancer cells—which is a tumor just large enough to be picked up by mammography.

Even though it has to double only 30 times, it takes between 25 and 1,000 days for cancer cells to double just once. So, that means from the time that first cell gets mutated, it takes between two and a hundred years before it shows up as a little tumor that we can see.

The shortest known interval between exposure to a carcinogen and cancer is about 18 months, which is when the first leukemia cases started appearing after Hiroshima. Cancers need time to grow, and for most solid tumors, meaning non-blood tumors like breast cancer, cancer can take decades to develop. Many breast cancers may start in the teen years. Some think we actually may start developing breast cancer in the womb before we’re even born, and that depends in part on what our mom ate. This is what’s called the promotion stage of cancer. Twenty years ago I ate meat, a lot of meat. I very well may have mutated one of the cells in my prostate, or liver, or colon. But you know, I don’t mind if I get cancer in a hundred years. I don’t expect to be around to worry about it. The cancer may have been initiated by a DNA mutation, but if we don’t promote it, if we keep it dormant, if we slow it down, we may even be able to reverse its growth.

According to autopsy studies in Japan, they’ve got just as much prostate cancer as we do, but the rate of Japanese men dying from prostate cancer is one tenth that of American men, till they start eating like us. Japan has the number one longest life expectancy of any nation. The U.S. falls around 19th. When Japanese men finally do die, though, many have tiny prostate tumors. But they die with their cancer, instead of from their cancer. By age 80, the majority of men have tiny prostate cancer tumors, and by age 40, one third of women have microscopic cancerous breast tumors. It’s like atherosclerosis. About half of young Americans in their twenties already have atherosclerotic plaques—hardening of their arteries.

Many of us right now have tumors growing inside of us; so, we can’t wait until later to start eating healthier. We have to start now. How can we slow down and reverse cancer while it’s still microscopic? Well, for prostate and breast cancers, these tissues tend to be sensitive to growth-promoting steroid hormones, like estrogen. So, one way to decrease our levels of these steroid hormones may be to stop eating and drinking them by avoiding eggs, meat, and dairy.

Okay, let’s get to the new research. UCLA scientists placed women on a plant-based diet with exercise, and the levels of all measured growth hormones in their blood dropped dramatically. That’s not new news. It’s what they did next that made this one of the most exciting papers to come from that conference. Before and after the dietary change was initiated, researchers drew blood from the women, and dripped it on live human breast cancer cells growing in a petri dish. After just two weeks, the blood of women on the plant-based diet reduced the cancer growth rate by 20%. This is before; just packed with cancer. This is after. Just two weeks on a plant-based diet, and the blood circulating throughout their entire bodies was that inhospitable to cancer. Again, many of us right now have tumors growing inside of us; so, we can’t wait until we’re older to start eating healthier. We have to start now, tonight.

"In the U.S., up to nearly one in three men in their 30s already have small prostate cancers brewing, and that grows to nearly two-thirds of American men by their 60s. On autopsy, most older men were found to have unknown cancerous tumors in their prostates. What's remarkable is that Asian men seem to have the same prevalence of these hidden, latent prostate cancers on autopsy, but the tumors don't t tend to grow enough to cause problems. In Japan, men tend to die with their tumors, rather than from their tumors. Of course, that's changing, as Asian populations continue to Westernize their diets."

"Early" detection is actually really late. Without mammograms, breast cancer may not be caught for an average of 22.8 years. With mammograms, though, breast cancer may only grow and spread for…21.4 years.

In my national best-selling book, McDougall’s Medicine—A Challenging Second Opinion, I presented this simple illustration and explained that breast cancer has, on average, been growing for ten years before discovery by any technique. The same picture is true for prostate cancer.

The argument for early detection of breast and prostate cancer rests on the belief that the test can discover cancer in its early stages—before it has spread to other parts of the body.  Unfortunately, this argument is groundless.  Many laypeople, and a very few physicians, believe that breast and prostate cancer goes through a series of steps in which it remains within the respective organs for some time period until it spreads to the lymph nodes and then to the rest of the body. In their minds the process looks something like this:

Step 1:  A cancer manifests and starts to grow slowly in the tissue (in this case, the breast or prostate).

Step 2:  With time, the cancer grows into a larger tumor.

Step 3:  Eventually, the cancer spreads to the lymph nodes.

Step 4:  Finally, the cancer spreads from the lymph nodes to the rest of the body.

This step-by-step progression from a harmless mass to a body full of disease almost never occurs.  Rather, cancer spreads to other parts of the body via the venous bloodstream in the very early stages of its development. The spread of cancer to the lymph nodes actually occurs simultaneously with the spread of the cancer to other parts of the body.

Normal, healthy cells multiply only when necessary, such as during childhood growth and development, or to repair damaged tissues after an injury.  Cancer cells, however, divide at their own free will at the site of origin, and spread to other parts of the body where they continue this uncontrolled growth without respect for the surrounding healthy tissues.  Like most other cancers, breast and prostate cancers begin with the mutation of a single healthy cell into a malignant one. Once this transformation occurs, the single cell begins to replicate, or divide. The time it takes one cell to divide and become two cells is called the doubling time. The average doubling time is approximately 100 days. ^3,8 This means that in 100 days, a single cancer cell will have become two cancer cells. In 200 days, that one cell will have become four cells in a breast or prostate gland. By one year there are eight to twelve cancer cells lurking undetectable. Consider that one breast or the entire prostate gland consists of about 100 billion cells, and then you know why the cancer is impossible to find.

At this doubling rate, it takes about six years for the single cancer cell to become one million malignant cells, which together form a tiny tumor that is about the size of the tip of a lead pencil. A mass of this size is less than one millimeter in diameter, and is undetectable by breast self-examination or mammography (or any other presently-known technology) in the female breast, and by digital rectal examination (DRE) or by PSA (or any other presently-known technology) in the male prostate.

Even though the cancer is so tiny that it cannot be detected, it nevertheless has already spread, or metastasized (in medical terminology), to other parts of the body in virtually every case of true cancer (as opposed to the latent forms of cancer). It is the cancer cells that have spread to, say, the liver, lungs, bones, and brain, that kill the patient, and not the cancer cells confined to the breast or prostate.

After about ten years of growth, the average cancerous mass inside the breast or prostate is about one centimeter in diameter, or about the size of an eraser on the end of a pencil, and consists of about one billion cells. This is the earliest stage at which a tumor can be found. As Dr. Gullino explains, “two-thirds of the duration of a breast cancer remains undetectable by the patient or physician.” ³ As you can see, early detection is a misnomer.