Aging muscle is less responsive to protein than young muscle. The same meal that sets off a solid building response in a thirty-year-old produces a weaker one at seventy. Researchers call it anabolic resistance, and it has been measured: in one study, older men needed about 0.4 grams of protein per kilogram in a single meal to get the response younger men got from 0.24. The practical consequence is blunt. An older adult needs more protein per pound than a younger one to get the same result, not less.

Two expert groups reviewed the evidence and said so. The PROT-AGE study group and, separately, the European Society for Clinical Nutrition and Metabolism both concluded that healthy adults over sixty-five need at least 1.0 to 1.2 grams of protein per kilogram of bodyweight a day, that anyone exercising needs more, and that illness pushes it to 1.2 to 1.5. The figure printed on packaging, 0.8 grams per kilogram, was set for the population as a whole and is below all of those. PROT-AGE added a second point that matters as much as the first: 25 to 30 grams at each meal, rather than a little at breakfast and a pile at dinner.

Meanwhile the appetite shrinks, the cooking gets harder, and the advice is to eat less. The requirement goes up while the intake goes down, and the muscle quietly disappears in the gap. That process has a name, sarcopenia, and I watched it turn into a walker, then a fall, then a broken hip, in patients for forty years.

So the number I use for anyone over sixty is 0.8 grams per pound of bodyweight, every day, lifting or not, with at least 30 grams at each of four eating occasions. If you are carrying a lot of extra weight, use your goal weight, or the number gets silly. For a 160-pound person that is about 128 grams a day, which sounds heroic until you split it: 32 grams is one ordinary chicken breast, or a cup and a half of plain Greek yogurt with a spoon of seeds, or a can of sardines with a cup of lentils. Four normal things, spread over a normal day.

Why four occasions rather than one big dinner: in the one direct comparison, the same daily protein eaten evenly across three meals produced a muscle-building rate over twenty-four hours about a quarter higher than the same total skewed toward dinner. Eight people, one day, a synthesis rate rather than muscle measured over months, so it is the reason for the rule rather than proof of the result. But past sixty the size of each meal matters more than the daily total, and if you are eating less overall, protein is the last thing to cut.

None of it works without load. Muscle responds to real demand at any age; the classic study put nursing-home residents in their nineties on eight weeks of strength training and their leg strength rose by about 170 percent. What changes after sixty is recovery, which takes longer, and technique, which matters more. If you have kidney disease, the protein number is a conversation with the physician who manages it, not a rule from a book. Chapter six of The LP3 Diet has the number worked through for three different people, and chapter eight has the training that goes with it.

Four ounces of cooked skinless breast gives you about 35 grams of protein whichever bird it came from. Turkey breast carries about 2 grams of fat and chicken breast about 4, and that is the whole difference between them. It is a real difference, but it is small next to everything else on the plate.

The skin is a different story. Leave it on a chicken breast and the fat roughly doubles, from about 4 grams to 9, with no more protein to show for it. A thigh without its skin gives you about a fifth less protein than a breast for more than twice the fat. With the skin on, four times the fat. Between a quarter and a third of the fat in poultry is saturated, whichever part of the bird it comes from, so more fat means more of the kind that shows up in a cholesterol result.

So far, so simple: skinless breast, either bird. The place people go wrong is the ground meat, because there the label works against you.

Ordinary ground turkey is not ground turkey breast. Under the federal labeling rule it may contain dark meat as well as white, and the skin and its fat go in too, in the proportions they occur on the bird, unless the label says otherwise. The “93% lean” on the front is measured raw. Cook it, and the water goes while the fat stays, so four ounces of cooked 93% lean ground turkey carries about 13 grams of fat. That is more than a chicken breast with the skin on. The 85% lean kind cooks to about 20 grams. Ground chicken, unless the package says breast, comes in around 12.

The pack you want says ground turkey breast, usually with 99% fat-free on the front. It cooks to about 3 grams of fat in four ounces, which is why it is the one the recipes in my book call for. If the front of the package is ambiguous, turn it over: on the Nutrition Facts panel you are looking for two grams of fat or less per four-ounce serving. Anything showing eight or ten grams raw is the ordinary kind, whatever the front says about lean.

None of this means dark meat is a bad food. It means that if the reason you are eating poultry is to get a lot of protein without much saturated fat, and on the LP3 plate that is exactly the reason, then the breast does the job and the rest of the bird does it less well. A thigh now and then is not a problem. A pound of 85% lean ground turkey every week, bought in the belief that it was the lean choice, is the kind of quiet mistake that adds up over years.

The figures above are averages from the USDA’s food composition database, per hundred grams and scaled to four cooked ounces. A given bird or brand will differ by a gram or two. Chapter three of The LP3 Diet has the full comparison, cut by cut, in one table.

Flavored is different, and the question I get asked is whether there are flavored tubs that are not, in effect, dessert. There are a few. Finding them takes the label, not the front of the package, and four things have to be true at once.

First, no fat. The fat in dairy is mostly saturated, and the whole point of choosing Greek yogurt over cheese is to get the protein without it. Second, zero grams of added sugars, the line on the Nutrition Facts panel that reads “Includes 0g Added Sugars.” Total sugars will not be zero, because milk has its own, and that is fine. Third, at least twelve grams of protein in a single-serve tub. Some flavored yogurts are thinned out with fruit preparation until the protein is not worth the calories. Fourth, none of these three words in the ingredients: sugar, fructose, erythritol.

Sugar and fructose are on the list for the obvious reason. Erythritol is there for a less settled one. In 2023 a group at the Cleveland Clinic found that people with the highest blood levels of erythritol had more heart attacks and strokes over the following three years than people with the lowest, and that erythritol made platelets, the cells that start a clot, more reactive in the laboratory. A follow-up in healthy volunteers found the same platelet effect after a single 30 gram drink. That is an association in people who were already under cardiac evaluation, plus a small study of one large dose. It is not proof that the amount in a yogurt does anything. But I have spent forty years watching open questions about the heart resolve in unwelcome directions, and stevia, monk fruit and allulose do the same job without it. Sweeteners in general are worth a caution of their own: the World Health Organization now advises against relying on them to control weight or lower disease risk, on evidence it rates as low certainty.

At the time of writing, only a couple of flavored Greek yogurts sold nationally pass all four tests. I have not named them in the book, because formulations change and a rule you can check on the label outlasts any list of brands. If a tub in your hand shows no fat, zero added sugars, twelve grams of protein or more, and none of the three words in the ingredients, it is acceptable. Most flavored tubs fail on the second test alone.

And the better bowl is still the plain one. Fat-free plain Greek yogurt with berries and cinnamon has more protein than any flavored tub, no sweetener question to think about, and fruit that arrives with its fiber. That is the breakfast the plan calls for most mornings, and the flavored exception is exactly that: an exception, for the days when plain is not going to happen.

The yogurt rule is one line on the food list in The LP3 Diet. The rest of the list is built the same way, each item there because of what it does for the arithmetic of protein against saturated fat.

At the top end, fiber slows things down. The soluble, gel-forming kind in oats, barley and beans makes a meal leave the stomach and get absorbed more gradually. That blunts the rise and crash in blood sugar that leaves you rummaging in a cupboard at four in the afternoon, and it is most of why a bean-heavy lunch holds you until dinner and a sandwich does not. A 1978 experiment showed the effect directly: adding viscous fiber to a glucose drink flattened the blood-sugar curve, and the flatter curve tracked how viscous the fiber was.

At the bottom end, fiber speeds things up. Further down, it adds bulk and holds water, and a sluggish bowel moves faster. It does not push a regular one into overdrive. It tends to bring both extremes toward normal, which is the part of the story that was worked out by a surgeon who counted stools.

Denis Burkitt was an Irish-born surgeon whose name is on the lymphoma he described in Uganda. He spent his later career on a different puzzle: why the bowel diseases filling Western hospitals were rare where people still ate traditional high-fiber diets. With Alec Walker, a South African researcher who had been timing gut transit for years, and the surgeon Neil Painter, he recorded more than a thousand transit times and weighed what came out. Unrefined diets produced large, soft stools that moved through quickly. Refined Western diets produced small, firm ones that took days. The paper was published in 1972.

The next year another group put twenty people on extra bran or a high-fiber diet and timed them. The slow ones sped up, from about 3.8 days to 2.4. The unusually fast ones slowed down. Fiber pulled both toward the middle. A 2016 review of ninety-three later studies put a number on it: where transit started at 48 hours or more, each extra gram of fiber a day shortened it by about half an hour, and where it was already faster than that, fiber did not change it.

Fifty years on, that part of Burkitt’s work has held up well. So has a lower rate of diverticular disease in the people who eat the most fiber: in a British cohort followed for a decade, the highest fiber intakes went with about forty percent less risk of being admitted to hospital with it.

The cancer part is more complicated, and I would rather say so than let the good half of the story carry the weak half. Large population studies find about ten percent less colorectal cancer for every extra ten grams of fiber a day. But the two big trials that gave people bran or a high-fiber diet did not stop polyps coming back in people who had already had them removed. Polyps over three or four years are not cancer over decades, and the trials were small next to the cohorts. The honest summary is that fiber probably lowers the risk, that the case rests on observation rather than experiment, and that nobody should eat oats expecting them to undo a colonoscopy finding.

What fiber also does, and this matters for the muscle half of eating well, is fill you up. On a plate where half or more is plants, fiber is the reason you can eat until you are full and still lose fat rather than muscle. That is the mechanism The LP3 Diet is built on, and chapter two tells the rest of this story.

The most direct test that exists says yes. In 2021 a group in Brazil took nineteen habitual vegans and nineteen omnivores, young men, and put both groups through twelve weeks of supervised resistance training. The important part is that they brought both groups to the same protein intake, about 1.6 grams per kilogram of body weight a day, the vegans with soy protein and the omnivores with whey. Then they measured the muscle.

Muscle cross-sectional area rose 2.2 square centimeters in the vegans and 2.8 in the omnivores. Leg-press strength rose 97 kilograms and 117. Neither difference was statistically significant, and the authors concluded that the plant-based diet was not different from the mixed one for building muscle and strength, as long as the protein was there.

That last clause is the whole finding. The vegans in that trial did not build muscle because plants are magic. They built it because someone made sure they ate 1.6 grams per kilogram, which is well above what most people eating mostly plants get on their own. Take the supplement away and you are back to the worry in the first paragraph.

Two things about plant protein make the number harder to hit. Plant proteins are generally lower in leucine, the amino acid that acts as the trigger for building, so a plant-heavy meal usually needs to be a somewhat larger meal to send the same signal. And they come packaged with a great deal of fiber, which is a feature until it becomes the thing stopping you eating enough. Anyone who has tried to get forty grams of protein from lentils in one sitting knows the second problem.

There is also a small, consistent finding on the other side of the ledger. Across thirty randomized trials in some 1,538 people, animal protein showed a modest advantage over plant protein for muscle mass, with no significant difference for strength or physical performance. Small, but it is the reason the LP3 plate is not a vegan one. It puts plants first, half the plate or more, and then layers lean protein on top: chicken and turkey breast, egg whites, fat-free Greek yogurt, and fish, alongside the legumes and tofu. That is how you get the protein without much saturated fat coming with it, which is the other half of the problem: the half that catches up with people who are otherwise fit, as it caught up with me.

So the answer is yes, with a condition. A plant-based plate builds muscle when the protein is deliberately there, and most of the time it is not. The trial was thirty-eight young men over twelve weeks, which is the most direct evidence we have and not the same as a large amount of it. If you are older, the number goes up, not down, and the margin for getting it wrong shrinks.

How much protein, on how many occasions a day, and what actually contains it is chapter six of The LP3 Diet, with the worked examples.