Eat only every other day and lose weight?

The alternate-day fasting thing is very popular right now. This gist of it is, basically, feast and famine. You starve one day, then feast the next. Proponents claim that this approach will lead to weight loss, as well as a number of other benefits.

As a physician researcher, this annoys and alarms me. I preach sensible intake of real foods as part of a lifelong approach to health. I also depend on scientific evidence to guide my counseling. So, I welcomed this yearlong study comparing alternate-day fasting with more common calorie restriction.
Some data on alternate-day fasting

Researchers divided 100 obese study volunteers (mostly African-American women, without other major medical issues) into three groups:

    one group followed an alternate fasting plan, which meant on the fasting day they would eat only 25% of their caloric needs and on the non-fasting day they’d eat a little bit more (125% of their caloric needs per day)
    a second group ate 75% of their caloric needs per day, every day
    a third group ate the way they typically did, for six months.

The two diet groups received counseling as well as all foods provided. This “weight loss” period was followed by another six months of “weight maintenance” and observations.

Both diet groups lost about 5.5% of their body weight (12 pounds) by month six, and both regained about 1.8% (four pounds) by month 12, and had significant improvements in blood pressure, blood sugar, insulin, and inflammatory proteins when compared to the people who ate their normal diets.

At the end of the 12 months, there was only one difference between the two diet groups: the alternate fasting day group had a significant elevation in low density lipoprotein (LDL), an increase of 11.5 mg/dl as compared to the daily calorie restriction group. LDL is known as a risk factor for heart attacks and strokes, so that’s not good.
And how would this work in real life?

This was a very small study to begin with, and, more importantly, there was a fairly significant dropout rate. Only 69% of subjects stayed to the end, which decreases the power of the findings. Twelve people quit the alternate-day fasting group, with almost half citing dissatisfaction with the diet. By comparison, 10 people quit the daily calorie restriction group, and none cited dissatisfaction with diet, only personal reasons and scheduling conflicts (eight quit the control group for the same reasons).

It’s not surprising that people disliked alternate-day fasting. Previous studies have reported that people felt uncomfortably hungry and irritable on fasting days, and that they didn’t get accustomed to these discomforts. Interestingly, in this study, over time people in the fasting group ate more on fasting days and less on feasting days. So basically by the end of the study they were eating similarly to the calorie restriction group.

The authors note more limitations. The control group did not receive food, counseling, or the same attention from the study personnel, potential factors that could affect their results, besides how they ate. And this study can’t tell us about the potential benefits for people who have high blood pressure, high cholesterol, or diabetes because the study didn’t include individuals with those conditions.
The bottom line

Usually at this point we say something like “more studies of this approach are needed,” but I won’t. There’s already plenty of evidence supporting a common-sense lifestyle approach to weight loss: ample intake of fruits and veggies, healthy fats, lean proteins, and plenty of exercise. From apples to zucchini, there are over a hundred “real” foods you can eat endlessly, enjoy, and yes, still lose weight.

I would advise against spending any more money on fad diet books. Or processed carbs, for that matter. Rather, hit the fresh or frozen produce aisle, or farmer’s market, and go crazy. Then go exercise. Do that, say, for the rest of your life, and you will be fine. No one got fat eating broccoli, folks. (That said, if you tend to binge or stress-eat sugary or starchy foods, and you feel like you can’t control your habit, talk to your doctor, because that is a separate issue to be addressed.)
In 2012, the US Preventive Services Task Force (USPSTF) took the unprecedented step of recommending against prostate cancer screening for all men, regardless of age, race, or family history. Now this influential group of independent experts is reassessing its position based on more recent data. Instead of discouraging screening altogether, the UPSTF is urging doctors to discuss its potential benefits and harms with men 55 to 69 years of age. The same recommendation applies to all men in this age group, including those at higher risk of prostate cancer, such as African Americans and men with a family history of the disease. The USPSTF continues to recommend against screening men older than 70, since they’re unlikely to experience a survival benefit from treatment during their expected lifespans. The USPSTF was silent on men younger than 55, because Task Force members don’t believe there is sufficient information for them to make a recommendation.

Screening is usually done with a blood test that measures levels of a protein released by the prostate gland called prostate-specific antigen, or PSA. Elevations in PSA may be due to prostate cancer, but other conditions can also cause levels to rise, such as inflammation or an enlarged prostate. PSA levels also vary from man to man and can be unusually high in men who are otherwise healthy. To confirm or rule out a cancer diagnosis, doctors will typically order a biopsy of the prostate. However, prostate biopsies can lead to complications like infection, bleeding, and pain, and they often detect slow-growing, low-risk cancers that may never cause a man any harm during his lifetime. Treating low-risk cancers can leave men impotent and incontinent for years without extending their survival.

The USPSTF recommended against screening five years ago because its members felt the harms of treatment outweighed the benefits. However, newer data make the tradeoffs between potential harms and benefits too close to call. A European study published in 2014 found that PSA tests can prevent three cancers from spreading, and prevent one to two prostate cancer deaths, for every 1,000 men screened over 13 years. Then a study published last year found no difference in 10-year survival among men who were monitored or treated for low-risk prostate cancer. Monitoring, which is also called active surveillance, entails periodic PSA tests and biopsies to check for cancer growth, and thus allows men with low-risk prostate cancer to avoid the harms of treatment, at least temporarily.

It’s important to emphasize that the Task Force is not recommending that men in the 55-69 age group be screened, only that they talk about it with their doctors and then decide personally if it’s something they want to do, in accordance with their own values and preferences.

“Even the most serious student of prostate cancer and prostate cancer screening can appreciate the enormous endeavor that the Task Force undertook,” said Dr. Marc Garnick, the Gorman Brothers Professor of Medicine at Harvard Medical School and Beth Israel Deaconess Medical Center, and editor in chief of “Patients should consider shared decision making with their health provider when it comes to screening. But as in 2012, the ability to show an overall survival benefit from any screening recommendation still eludes us, and the cancer-specific survival benefit, if one exists at all, is at best very modest.”
In April, scientists reported encouraging results from a pilot study of men with metastatic prostate cancer, or cancer that has spread beyond the prostate gland. Long considered incurable, these advanced cancers are usually treated by giving men systemic drugs that target new tumors forming in the body. The scientists who led this new study took a more aggressive approach. In addition to giving systemic therapy, they surgically removed the prostate gland and affected lymph nodes, and also treated visible cancer in the bones with radiation. By throwing everything but the kitchen sink at these cancers, they achieved a stunning result: some of the treated men are still cancer-free after four years, and one has lived without evidence of cancer for five years. “If these remissions persist long enough, then we have to ask whether some of these men have been cured of their disease,” said the study’s lead author, Dr. Matthew O’Shaughnessy, a urologic oncologist at the Memorial Sloan Kettering Cancer Center, in New York.
How the study was conducted

The small pilot study enrolled 20 men, and O’Shaughnessy emphasized that follow-up with a larger group is needed to confirm the results. Five of the men had cancer that had spread to lymph nodes in the pelvis, and 15 of them had cancerous lesions in their bones. All the men were treated for between six and eight months with hormonal therapy, which blocks testosterone (the male sex hormone that makes prostate cancer cells grow faster). As noted previously, they also had their prostates and lymph nodes removed, and bone lesions were treated with radiation as needed. What the researchers were aiming for is a complete absence of prostate-specific antigen (PSA) in blood for a minimum of 20 months after the start of hormonal therapy. Prostate cancer cells will shed PSA into blood, but if the gland has been removed and all traces of cancer removed from the body, the levels should drop to zero and stay there, even after testosterone levels return to normal.

Overall, five men had undetectable PSA at 20 months and counting, although that number is too small to draw any conclusions about who might benefit most from the approach. According to O’Shaughnessy, when used together hormonal therapy, surgery, and radiation all contributed to prolonged remissions that would not have been possible if only one treatment was used. A study employing the same methods is planned for later this year.
What this means for treating advanced prostate cancer

Until recently, taking out the prostate and lymph nodes in men with advanced prostate cancer would have been unthinkable. Doctors worried that surgery could release cancer cells into the bloodstream, but newer studies show it can safely lengthen survival. Researchers have also been combining hormonal therapy and radiation with encouraging results, and now giving all three treatments is “consistent with a trend of doing more for advanced prostate cancer than doing less,” said Dr. Marc Garnick, the Gorman Brothers Professor of Medicine at Harvard Medical School and Beth Israel Deaconess Medical Center, and editor in chief of Still, Garnick cautions that cures for advanced prostate cancer can take decades to confirm. “Hopefully follow-up research will support this transformative approach,” he said.


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