https://scitechdaily.com/reducing-protein-in-diet-improves-health-and-extends-lifespan/ A Single Hormone Directs Body’s Responses to Low-Protein Diet. Mice live longer and lose weight while eating more when the hormone FGF21 is present. A single hormone appears to be responsible for the lifespan extension produced by a low-protein diet. A new study from Pennington Biomedical Research Center, published recently in the journal Nature Communications, found that reducing the amount of protein in the diet produced an array of favorable health outcomes, including an extension of lifespan, and that these effects depend on a liver-derived metabolic hormone called Fibroblast Growth Factor 21 (FGF21). It has long been recognized that reducing the amount you eat improves health and extends lifespan, and there has been increasing interest in the possibility that reducing protein or amino acid intake contributes to this beneficial effect. Several recent studies indicate that diets that are low in protein, but not so low that they produce malnutrition, can improve health. Conversely, overconsumption of high-protein diets has been linked to increased mortality in certain age groups. A few years ago, Pennington Biomedical’s Neurosignaling Laboratory discovered that the metabolic hormone FGF21 was a key signal linking the body to the brain during protein restriction. Without this signal, young mice failed to change their feeding behavior or metabolism when placed on a low-protein diet. “Our data suggest that FGF21 talks to the brain, and that without this signal the mouse doesn’t ‘know’ that it is eating a low-protein diet. As a result, the mouse fails to adaptively change its metabolism or feeding behavior,” said Christopher Morrison, Ph.D., Professor and Director of the Neurosignaling Lab. The group’s newest work, led by postdoctoral researcher Cristal M. Hill, Ph.D., demonstrates that low-protein diets produce beneficial metabolic effects in aged mice, improving metabolic health, reducing frailty, and extending lifespan. These beneficial effects were also apparent when protein intake was reduced in middle-aged mice, even protecting against the detriments of obesity. Importantly, these beneficial effects were lost in mice that lacked FGF21, suggesting that its action in the brain is critical for the increase in health and lifespan. “We previously showed that FGF21 acts in the brain to improve metabolic health in young mice fed a low-protein diet. These new data extend this work by demonstrating that FGF21 also improves metabolic health and extends lifespan. Collectively, these data provide clear evidence that FGF21 is the first known hormone that coordinates feeding behavior and metabolic health to improve lifespan during protein restriction,” Dr. Hill said. However, Dr. Hill said several questions remain. It’s unclear exactly how these observations will translate to aging humans, but the hope is that this work will uncover novel molecular and neural pathways that can be leveraged to improve health in people. “This groundbreaking research has important implications for extending the health and lifespan of people. If scientists can better understand how diets and nutritional hormones like FGF21 act to extend lifespan, these discoveries could offset many of the health issues that occur in middle age and later,” said Pennington Biomedical Executive Director John Kirwan, Ph.D.
This is annoying. I get that some caloric restriction can be a good thing so that people don't accumulate unnecessary fat over the course of their lifetime: https://www.elitetrader.com/et/thre...olism-immunity-for-longer-health-span.364896/ But now protein restriction for a longer, healthier life? Meanwhile, other sources preach the need for older adults to consume more protein because their aging bodies process protein less efficiently, and that they need it to help slow down age-related sarcopenia, which affects mobility in later years, and even cognitive decline: https://khn.org/news/why-older-adults-should-eat-more-protein-and-not-overdo-protein-shakes/ https://www.washingtonpost.com/nati...6926ce-1a78-11e9-88fe-f9f77a3bcb6c_story.html https://news.yahoo.com/eating-enough-protein-150729322.html So what's a boy to do?!
I think the longevity picture is much more complicated than these simplistic articles make it out to be. It's not just a matter of consuming a standard amount of protein. An older person who is active, exercises, works in the garden, etc. will require higher amounts than one who is sedentary. To me, the more important factor is actually on the carb side of the equation. We've learned from the Atkins diet that a person can consume large amounts of protein and lose weight due to low insulin levels. Remember, insulin is like the key that unlocks a cell's door to allow nutrients to be absorbed. So in my opinion the question is less about how much protein you're taking in and more about what carbs you're consuming along with that protein and how those carbs are raising insulin levels and affecting absorption. And that's when we get into the glycemic index, a person's insulin sensitivity and all that good stuff.
Simplistic maybe, but conflicting, too! Yes, meaningfully more active people will likely require some more protein. But some studies suggests that even the sedentary will require more protein, presumably above the RDA, as they get older because their aging bodies are no longer processing it as efficiently. Meanwhile, we now have studies suggesting a reduction in protein to enhance longevity, which presumably means below the RDA. Those are diametrically opposed conclusions. As for Atkins, I'm not sure we learned much other than what not to do. Most experts believe his was a diet for achieving shorter term weight goals and the appearance of good health at the expense of mortgaging long-term health and wellbeing. I agree that the kind of carbs we're eating makes a big difference. It is unfortunate that many people seem to group healthful carbs with junk carbs. They are distant cousins at best. Speaking only for myself, at least half of my calories come from carbs, none of which are junk carbs. I imagine the rest are split almost evenly between protein and fat. And I am fairly lean as I approach my 64th birthday later this summer. I don't look any different from the pics I posted almost 3 years ago, as I check myself after each workout. My BP is quite good and I am not on any meds. Baron, what is your macro breakdown? Ballpark.
A lot of those studies were based on attempts to deconstruct and replicate the diets of people that live to be older than 100 years old because in Okinawa for example, their diet is roughly 90% carbs. But again, it goes back to carb quality (which in their case is sweet potato), so you get a very high-quality,low-glycemic carb that has plenty of fiber, but it doesn't drive the pancreas into insulin release overload like white rice or white potatoes would. In terms of my macros, I prefer to take things on a plate-by-plate basis. So if I have a high-fat ribeye on my plate, I tend to pair that with a low-glycemic side item like a caesar salad. And conversely, if I have a very lean pork chop on my plate, I have no problem pairing that up with a baked potato or rice of some variety. The problem for most people is that they create the perfect storm of gaining weight by constructing their plates improperly. So an example of that would be going to the local steakhouse and starting out with the bread and butter. The bread raises insulin right off the bat, which conveniently opens up the cells to absorb the fat from the butter. Then they move on to eating salad covered in carb-packed croutons paired with a high-fat dressing, and then have a baked white potato covered in butter with a nice fatty and flavorful ribeye. The pairing of high glycemic carbs with high fat is a wonderful treat for the taste buds, but a recipe for weight gain every time, especially for those that are fairly sedentary.