Tag Archive for: cancer

Controversy: PSA Testing

/in /by

Medical testing is a blessing at times, a curse at others, and a source of controversy in the medical profession itself. I recently wrote about colonoscopies and why they provide information other colon health tests do not. The PSA (protein specific antigen) screening for prostate cancer has also been controversial. Here’s why.

If the PSA exceeds a specific number (another point of controversy), especially if a digital rectal exam reveals an enlarged prostate, more tests follow. The prostate biopsy takes samples of the prostate to see if cancer is present. If not present, the PSA was a false positive that resulted in a much more expensive test that probably increased the anxiety of the individual.

But wait—there’s more. Even if cancer is diagnosed, it may or may not indicate treatment. That’s because many prostate cancers are very slow growing, especially in elderly men, and will not impact how long they live. They may die with prostate cancer but not of prostate cancer.

How do you decide whether testing PSA is necessary? A new study may provide some direction, and I’ll cover that Saturday.

The Insider conference call is tomorrow night, and the topic is important: a recent study and the medical press that followed have indicated your ability to purchase dietary supplements may be under attack. If you’re an Insider, you don’t want to miss this call. If you’re not, purchase your Insider membership by 8 p.m. ET Wednesday night to get the latest information as well as all the other benefits of membership.

What are you prepared to do today?

        Dr. Chet

Science Says Coffee Is Good

/in /by

Research is based on curiosity; in order to do good research, you have to ask good questions. Researchers in the coffee study asked: Will a little sugar negate the benefits from drinking coffee? We don’t know whether this was the initial question or if researchers wanted to find out whether artificial sweeteners might have negative effects that altered the benefits of plain coffee.

Turns out artificial sweeteners did not have an impact on the mortality of those who used it over the seven years of the observational study. If you drink from one to 4.5 cups of unsweetened or sweetened coffee, there’s a reduction in mortality from CVD and cancer.

If artificial sweeteners did have an impact on mortality, the headlines would have been bigger than they were. Last week’s look at the safety of melatonin for kids led me to ask the author “Why melatonin?” Multiminerals in gummy form generally contain iron, and that can be toxic to toddlers in high quantities. So why not start looking there and then examine other nutrients? To date, I haven’t gotten an answer.

What Do We Mean by “Coffee?”

I explained how I drink my coffee earlier in the week. However for today’s coffee drinkers, there could be high-sugar flavors added as well as whipped cream and other assorted milks. It seems like a science unto itself to know how to order some of the “coffees” available today, let alone fill those orders. Based on what I read in the Methods section, the questionnaire they used didn’t go into that kind of detail. Extra sugar and fat from elaborate coffees may have a negative impact that won’t be determined in this study.

The Bottom Line

This was an observational study, so there’s no cause and effect implied. Still it’s good to know that the cup o’ Joe isn’t doing any harm and may actually be good for you. Now, about those tea drinkers…

What are you prepared to do today?

        Dr. Chet

Reference: Ann Internal Med. 2022. https://doi.org/10.7326/M21-2977

Coffee: One Sugar Please

/in /by

I have a strong relationship with coffee. I began drinking coffee when my mother put coffee in a bottle with a little sugar for me when I was a toddler. These days, a mother would get reprimanded by somebody if she did such a thing, but in the 1950s there weren’t the variety of drinks for children that are available today; milk, orange juice, and Kool-Aid, that was about it.

When I talk about coffee now, I don’t mean the fancy kind with steamed milk and espresso and other ingredients. I drink strong coffee, eight to ten ounces per mug, with exactly one teaspoon of sugar. I drink only Sumatra roast and use a Turkish grind, which is more like powder than grounds; I get the most flavor out of the beans when I brew it that way. I sit back and drink it, savoring every sip. (And yet somehow I married a woman who thinks the only thing coffee is good for is dipping a biscotti.)

The benefits of coffee have been established in prior studies of coffee drinkers compared to non-coffee drinkers. Coffee seems to reduce mortality from cardiovascular disease and cancer. No one seemed to separate the drinkers who used sweeteners from those who didn’t, and that’s why a recently published study caught my attention.

Researchers examined data from over 170,000 subjects in the U.K. Biobank Study; their purpose was to see if adding sweeteners to coffee, either sugar or artificial sweeteners, impacted the mortality of the subjects. I won’t make you wait until Saturday: the coffee sweetened with sugar had the same reduction in mortality as the unsweetened coffee. What about artificial sweeteners? I’ll talk about those on Saturday.

What are you prepared to do today?

        Dr. Chet

Reference: Ann Internal Med. 2022. https://doi.org/10.7326/M21-2977

How C-Reactive Protein Can Predict Cancer Risk

/in /by

High-sensitivity C-reactive protein (hs-CRP) is a measure of inflammation in the body. This blood test looks for inflammation that’s not apparent; with severe infection you have a fever, but other types of inflammation may go unnoticed. This is subtle because you don’t feel anything. On top of that, CRP hasn’t been shown to be diagnostic for any disease. It still may not be, but a recently published study demonstrated that there’s a chance that if CRP changes over time, that may be indicative of some forms of cancer.

The Study

The researchers examined the relationship between CRP trajectory patterns and new-onset cancers among 52,276 participants over eight years; CRP trajectories were developed from 2006 to 2010 to predict cancer risk from 2010 to 2019. The study was restricted to the population who participated in physical examinations in 2006, 2008, and 2010, and had their CRP measured each time.

If you can think of a variable, they tested for it, as well as collecting demographic information that allowed them to consider confounding variables in the statistical analysis. The subjects were tracked for the next eight years to find out who developed cancer and what type of cancer they developed.

The Results

During the extensive and complicated statistical analysis, four CRP trajectory patterns emerged:

A low-stable pattern (43,258 subjects)
A low-stable pattern was associated with a low risk of new cancers.

A moderate-increasing pattern (2,591 subjects)
Subjects in the moderate-increasing CRP trajectory pattern were associated with an elevated risk of any form of cancer, but especially lung, breast, leukemia, bladder, stomach, colorectal, liver, gallbladder, or extrahepatic bile duct cancer.

An increasing-decreasing pattern (2,068 subjects)
Subjects in the increasing-decreasing trajectory pattern were associated with an elevated risk of any form of cancer, but especially lung, breast, bladder, pancreatic, and liver cancer. This pattern was also associated with decreased risk of colorectal cancer.

An elevated-decreasing pattern (4,359 subjects)
Subjects with an elevated-decreasing trajectory pattern were associated with increased risk of leukemia and decreased risk of esophageal and colorectal cancer.

The Bottom Line

Here’s what we know now: inflammation is definitely one of the hallmarks of cancer. Regular assessment of CRP over many years may now be predictive as a risk factor for cancer but not diagnostic. There’s more research to go, but this study is a step in the right direction.

The good news is that it’s another risk factor that can be changed through lifestyle: Eat less. Eat better. Move more.

What are you prepared to do today?

        Dr. Chet

Reference: Int J Cancer. 2022. 10.1002/ijc.34012

Three Ways to Really Reduce Your Cancer Risk

/in /by

In the last Memo before Spring Break, I said I’d cover ways to reduce your risk of getting cancer that really work. Every cancer website has lists, ranging from 10 to 15 recommendations. I’m going to give you my top three ways to reduce the risk of cancer of the items you can control. You can’t control your age or your genetic risk factors, but there are many elements of your health you can control if you work at them.

I’m not including smoking cigarettes or other tobacco products. That’s a no-brainer and shouldn’t even be mentioned, because no one should smoke. (I’m not saying that from my perch on Mount Olympus; I smoked when I was young and foolish, and quitting was one of the best decisions I ever made.)

Dr. Chet’s Top Three Ways to Prevent Cancer

  1. Eat more vegetables and fruits every day and the wider the variety, the better. They don’t have to be organically farmed; you just have to eat eight to ten servings per day. That seems like a lot, and I’m not perfect at it, but you get a new chance every day. Here’s a tip: weigh your produce instead of measuring it. Find out what constitutes a serving in grams or ounces. You may find out that a large banana is actually two servings. Do supplements matter? Yes, but the important point is to eat the fruits and veggies first, then add a multivitamin as backup.
  2. Exercise for 30 to 45 minutes per day. The fitter you are, the lower your risk of cancer. It doesn’t all have to be aerobic; yoga and strength training count as well.
  3. Reduce your weight until you achieve as close to a normal BMI (under 25) as you can; you’ll find all the info you need in the Body Mass Index article on the Health Info page at drchet.com, including how to adjust your target for your body type. We talked about caloric restriction in February, and that’s a way to slowly reduce your weight. My theory is that the older you are, the more movement matters, so if you are doing well at Numbers 1 and 2, you’re well on your way to accomplishing Number 3.

Those may sound very familiar: Eat less. Eat better. Move more. The reason these are my top three is that they reduce inflammation in different ways.

On Thursday, I’m going to cover a study on the relationship between a test for inflammation and cancer.

What are you prepared to do today?

        Dr. Chet

Listen to Dr. Dog

/in /by

When I’m traveling, I often scan the airline magazine. This past weekend, I found an intriguing article about dogs and disease.

A woman had an unexplained weight gain after she moved across country several years ago. She also had repeated UTIs, bladder infections, and abdominal pain unexplained by digestive issues. She was treated and seemed to recover, but her husky kept sniffing her abdomen. She tired of it and shooed the dog away, but the dog would hide in the back of a closet whimpering. When her abdominal pain came back, she put two and two together because of the dog’s actions and sought a further diagnosis. She was diagnosed with stage three ovarian cancer. It’s returned once and the dog acted the same way.

In another case, a women’s dog kept trying to bite the back of her calf. She finally looked at the area and found a dark spot. She had melanoma.

The ability of dogs to smell thousands of times better than we can seems to be related. Cancer releases proteins that dogs can smell. I’ve got more to research on this but for now, if your dog is trying to tell you something in some strange way, listen.

What are you prepared to do today?

        Dr. Chet

Reference: Southwest Travel Magazine. 02-2020.

How Methionine Affects Cancer Treatment

/in /by

If you’ve ever been diagnosed with cancer and you start searching the Internet, one of the things that you’ll come across is using a vegetarian diet to help treat the cancer. I’ve recommended it myself combined with conventional treatment. The question is why? Yes, the phytonutrients from plants are healthier, but is there something in animal products that’s detrimental?

A research group examined the impact of the amino acid methionine on a pathway of one-carbon metabolism; this pathway is the target of a variety of cancer interventions that involve chemotherapy and radiation. They demonstrated that removal of methionine from the diet of mice and humans resulted in more effective treatment in two types of cancer. Chemotherapy and radiation were more effective in both types of cancer once the diet was changed.

There are a couple of important points. First, this was tested on only two types of cancer. There’s no reason to think it would benefit every type of cancer treatment because this one-carbon pathway is not a target for every treatment. Second, because methionine is found in all meat and seafood, it would mean giving up all meat for the duration of treatment.

For myself, I’d give up meat and seafood during treatment whether we have the research or not. It wouldn’t have to be forever and combined with giving up refined carbs to reduce the risk of C diff, it could lead to a better chance for treatments to work. And that’s the key. It’s not in place of treatment; it’s combined with treatment. The goal is to put the odds in your favor. This seems like a simple way to do that.

What are you prepared to do today?

        Dr. Chet

Reference: Nature Vol 572: 397–401 (2019).

The Bottom Line on Sugary Drinks and Cancer

/in /by

The question is simple: do we avoid all sugary drinks, including fruit juices? The best I can come up with is to withhold judgment and don’t get excited about it for now. Let’s take a look at what the concerns of the researchers were and then my concerns.

Researchers’ Concerns

The first is that the NutriNet-Santé study was not a randomized sample. That means that only those people who were interested in participating for whatever reason did so. The sample was predominantly women at 78.7% of the cohort with a mean age of 42 years. The researchers accounted for age and gender in the statistical analyses, but that doesn’t account for the lack of randomization.

Researchers also stated that the rate of cancer was much lower: 620 of the 100,000 people in the study compared with 972 per 100,000 people in all of France. They adjusted the numbers to reflect the age and gender distribution in France, but I used the numbers actually given in the study. They also said the diagnosis of cancer was self-reported. I can’t believe anyone would say they have cancer if they don’t, but it would have been better if it were verified.

Related to that, some cancers were limited, thus affecting the statistics. If you don’t have enough of any type of cancer, it’s difficult and scientifically shaky to calculate a relationship.

Younger subjects consumed higher amounts of sugary drinks than older subjects. There were other factors as well, but these also were taken care of statistically. Further, they acknowledge what I alluded to: when people self-report, they can over- and under-estimate their intake. They also chose only the subjects that had at least two diet records completed in the first two years; the potential was 10 if all records were completed by all subjects. That seems low to me—there’s too much missing data.

Finally, this was an observational study and thus cause and effect can’t be attributed to the results. But it does raise questions.

My Questions

I think they could have gone a long way to answering the question about sugar intake if they had compared the fruit intake with the juice intake: take the fruit intake, calculate the sugar content, then match it with juice intake with the same sugar content. What was the rate of cancer in each group? Doing the direct comparison could go a long way to suggest whether it’s the sugar alone or if the effects were ameliorated with the fiber and phytonutrients of whole fruit with the same amount of sugar. That’s an obvious question; this is an ongoing study so maybe they’ll do that in the future.

I also think that running a comparison of total carbohydrate intake could also give us insight. If someone had a high carbohydrate intake, especially if it were high in refined carbohydrates, that might be meaningful as well.

The Bottom Line

The question I was left with was this: how could less than a half-cup per day of any type of added sugary drink that contained fewer than 50 sugar calories cause an increase in cancer? It just doesn’t make any kind of sense when you consider the total mean average calorie intake of the subjects was 1,850 calories. If the total sugar intake from solid foods of the individuals was high, or it was highly refined carbohydrates, that could make a difference. That analysis wasn’t done.

At this point, I wouldn’t stop drinking a glass of fruit juice or adding some juice to a smoothie. Don’t go out of your way to drink more fruit juice, but don’t avoid it either; certainly you should choose fruit juice from whole fruit over soda with sugar. If you have an artificial sweetener you like, use that instead of sugar. As for other drinks that contain sugar, they’re highly refined carbohydrates so you should be keeping those under control anyway. While this was an interesting and controversial report, nutrition is still about balance. Keep that in mind as you choose what you eat and drink every day.

What are you prepared to do today?

        Dr. Chet

Reference: BMJ 2019; 366 doi: https://doi.org/10.1136/bmj.l2408.

Finding the Cancer Risk in Sugary Drinks

/in /by

In Tuesday’s Memo, I reviewed the methodology of the NutriNet-Santé study in France. As I suggested, it was solid. The sugary drink choices included fruit juices, sodas, sugar-sweetened hot and milk beverages, sports drinks, and energy drinks. In terms of the data collection, I can’t think of anything they could have done better.

Turning to the statistical analysis, it was complicated to say the least. The use of high-speed computers allows for many statistical analyses to be done in short order, even with over 100,000 subjects. My only concern is that, as they did the trend for hazard ratios, they adjusted for many variables including age, gender, energy intake, and family history. How many variables? About 24 in all by my count. That’s not necessarily wrong, but there are some that would seem obvious such as total carbohydrate intake from all foods, and percentage of calories from carbohydrates other than vegetables and fruit.

Another way of analyzing the data was something I’ve done before, and that’s compare the rate of cancer to the national cancer statistics in France. In this case, the rate of cancer in France is 0.95% while it was 0.87% in the unadjusted data from the study. That’s very close and a bit lower than the national average.

Must we avoid even a half-cup of fruit juice per day? Is the sugar in your coffee or sweet tea causing a significant increase in your risk of getting cancer? I’ll let you know on Saturday.

What are you prepared to do today?

        Dr. Chet

Reference: BMJ 2019; 366 doi: https://doi.org/10.1136/bmj.l2408.

Is There a Link Between Sugar and Cancer?

/in /by

Sugar has been in the news with the publishing of the latest results from the NutriNet-Santé study from France. The headlines of press releases suggest that drinking as little as four ounces of a sugary drink, including fruit juice, per day was related to an increased risk of getting cancer. Sugary drinks of all types except fruit juice were associated with an increased risk of getting breast cancer. These were all hazard ratio trend analyses; as the consumption increased, so did the risk of cancer.

If you read the Memos regularly, you know my approach is to always check how the data were collected. In this study, they used three 24-hour dietary records that included two weekdays and one weekend day. The diet records were done every six months throughout the duration of the follow-up, about five years. They subjects entered their data online; with over 100,000 subjects, that’s the only way this study could be done.

Of all the types of diet assessments, this is as close to the gold standard as I’ve seen. They had 97 different sugary drinks and 12 artificially sweetened drinks that were possible choices with very detailed descriptions and photos of drinks to help assess portion size. The only step they didn’t take was to have the records checked by a dietician before the subjects entered their data online. The methods in this study were solid compared to just about every other study I’ve talked about.

Should we avoid all sugary drinks at this point? More on Thursday. Tomorrow is the July Insider Conference call; this is your chance to learn more about nutrition and get your questions answers. You can still be included, so check out memberships right now.

What are you prepared to do today?

        Dr. Chet

Reference: BMJ 2019; 366 doi: https://doi.org/10.1136/bmj.l2408.