The New York Times recently posted an article which leans heavily towards the notion that people are now consuming protein at levels that are not healthy or safe. As is customary for New York Times health and science pieces, this article is full of oversimplifications, selective interpretations and omissions. Below is my brief takehome summary of the article, followed by specific article statements (in bold) and my responses (plain text).
The Takehome: This NY Times article largely tries to make a case for there being too much protein in people’s diets and also that these high levels of protein are unhealthy. This type of slant for an article is a disservice to the public because it is known that too much of any macronutrient can be unhealthy for a variety of reasons. What would be helpful is knowing how much protein exactly is too much for specific types of individuals. Of course, this is where research falls short and where this article turns a blind eye. We don’t have enough science controlling for individual factors and protein intake, but we know for a fact that significant muscle mass is lost in aging and higher than daily recommended allowances of protein are essential when exercising. Further, protein is expensive. So, odds are, too much protein is likely not massive societal problem (certainly not compared to the over-consumption of sugar). Indeed, most of the clients I train come to me very thin/frail and eating very little protein.
Specific Article Statements:
1. “The vast majority of Americans already get more than the recommended daily amounts of protein from food…and there are no rigorous long-term studies to tell us how much protein is too much.”
Recommended daily amounts of protein are notoriously vague. They don’t take into account age, sex, current lean mass, activity level, or target lean mass (if trying to gain muscle). As far as long-term studies are concerned, there are very few of these that exist for anything. Regardless of the factor being studied (food, supplements, drugs), it’s very hard to conduct long-term studies. If you only plan to consume products that have long-term studies backing their safety, you’re going to have a hard-time finding things to eat.
2. “You can eat 300 grams of protein a day, but that doesn’t mean you’ll put on more muscle than someone who takes in 120 grams a day,” Mr. White said. Meanwhile, “you’re robbing yourself of other macronutrients that the body needs, like whole grains, fats, and fruits and vegetables.”
You’re only robbing yourself of other macronutrients if you are reducing your intake of those other macronutrients. Just because an individual increases the amount of protein in their diet, doesn’t mean they are reducing the levels of other macronutrients. This has to be examined on a case-by-case basis.
3. “…a recent small trial found that older women who lost weight on a high protein diet did not experience one of the important benefits that usually follow weight loss, an improvement in insulin sensitivity, which reduces the risk of developing Type 2 diabetes.”
The study cited found this phenomenon in older obese women who were given a hypocaloric diet. That is, they tested high protein in women who were eating low calorie diets to lose weight. So, they were mixing two variables, caloric restriction and high protein. They do not separate out these effects. And of course, for those not overweight, this study does not have relevance.
4. “Large population studies also suggest an association between habitual high protein intake and a heightened risk of diabetes.”
The NY Times doesn’t give citations for these studies, so this doesn’t help clarify anything.
5. “Doctors also have concerns about the long-term effects of maintaining a high protein diet. Studies show that protein-rich diets do not preserve muscle mass over the long term, and doctors have long cautioned that a high-protein diet can lead to kidney damage in those who harbor silent kidney disease by putting extra strain on the kidneys.”
Again studies here are not cited. To the next point, yes certain doctors have concerns, but these concerns are only loosely based on science. High protein is a potential issue for individuals who have kidney problems – a special case scenario. If we’re going to take the stance of cautioning everyone away from “high” protein because they might harbor a silent disease…well, this just isn’t being done for the millions of other potentially hidden diseases/conditions that may be exacerbated by dietary factors. This just isn’t how medicine works.
6. “Furthermore, some researchers worry that the muscle building properties that consumers seek in protein may be a double-edged sword, perhaps even leading to an increased risk of cancer.”
This is a possibility (based largely on animal and cell culture studies), but we need more data. We need to better understand in what populations and in what doses this phenomenon may exist.
7. “Several large observational studies have linked high-protein diets with an increased incidence of cancer, heart disease and other ills. One study led by Valter Longo, the director of the Longevity Institute at the University of Southern California in Los Angeles, followed a nationally representative sample of 6,381 adults. It found that those who ate a high protein diet between the ages of 50 and 65 were four times more likely to die of cancer than those who consumed less protein.”
Yes, but the author of this NY Times article conveniently leaves out other data from this same study which indicate that high protein intake was associated with reduced cancer and reduced overall mortality in respondents over 65 years old. So, again, the data is not yet clear.
8. “Consumer groups have warned about the potential contamination of protein products, which are categorized as dietary supplements and loosely regulated. A Consumer Reports test of 15 protein powders and drinks in 2010, for example, found arsenic, lead, cadmium and mercury in some of the products tested.”
These metals are found of lots of foods in trace amounts. Were the levels found excessively high? Again, citations are not given for this study. The lack of regulation of supplements is a legitimate concern (as I’ve discussed previously), but there are good quality protein supplements out there which are tested for purity by independent third parties. So, this concern can be mitigated.
9. “‘Nothing beats real food,’ Mr. White said.”
Finally, a statement I agree with. The bulk of your protein should come from meals, but if you’re someone who is having trouble getting enough protein on a daily basis, supplementation is something I would recommend. Consuming 1g of protein per lb of body weight (or target body weight if trying to gain muscle) daily is a general guideline that continues to work very well to this day.