Dear Mark: Preventing Age-Related Muscle Loss, Sprouted Barley-Fed Meat, and a Pistachio Downside

For today’s edition of Dear Mark, we’ve got three questions and three answers. First up is a question from Casey, whose father is losing strength and muscle despite maintaining an active lifestyle. What can he do — dietarily and otherwise — to staunch and reverse the losses? Next, Australian cattle farmers are increasingly turning to sprouted grain as a replacement for standard grain feed. How does it compare to pasture feeding? Are there nutritional differences between sprouted and regular grain fodder? And finally, what do we make of the recent study showing negative effects in cyclists who ate a high-pistachio diet for two weeks? Should we rethink our stance on pistachios — and nuts in general?

Let’s go:

Dear Mark,

My father (64, fairly lean, very healthy given his diet) mentioned to me yesterday that he feels like he’s losing muscle and strength. He mostly follows what you recommend for exercise with lots of slow movement every day, but also mild strength training every day am/pm for work, so that’s non-negotiable. I looked, but had trouble finding much information about muscle loss from you and was wondering if you could write about it a little further. Thank you!!


Protein is key, and becomes even more vital the older a person gets. The protein RDA simply does not suffice for older people, who lose thigh muscle mass and exhibit lower urinary nitrogen excretion when given the standard 0.8 g protein/kg bodyweight. They’re just less efficient at processing, metabolizing, and turning protein into muscle. More recent studies indicate that a baseline intake of 1.0-1.3 g protein/kg bodyweight or 0.5-0.6 g protein/lb bodyweight is more suitable for the healthy and frail elderly to ensure nitrogen balance

He sounds pretty active, too, and that will increase the amount of protein he needs. I wouldn’t expect massive gains or anything. But moderate gains, especially in strength, and putting a stop to the loss of muscle is extremely realistic — and important for a healthy rest of life. Evidence suggests that increasing protein can both improve physical performance without necessarily increasing muscle mass and, if you’re into that sort of thing, increase muscle mass when paired with extended resistance training in the elderly.

Look at overall calorie intake, too. Low-calorie diets often lead to muscle and strength loss even when protein is high. If he’s active all day long, he just needs more food — not just protein. Make sure he’s consuming adequate calories to ensure weight maintenance. He shouldn’t be losing weight, unless it’s excess body fat which it doesn’t sound like he even has. In the elderly, weight loss tends to portend ill health. He needn’t fear a moderate amount of carbs, either. Since he’s lean, he can get away with healthy Primal carb sources like potatoes, sweet potatoes, winter squash, fruit, and even rice on occasion.

This is a longshot and it may be a little controversial, but testosterone replacement therapy is a viable (and totally understandable/justifiable) option for older men with waning strength, muscle loss, lower libido, and other symptoms of low testosterone levels. He’d have to talk to his doctor about that, of course. I suggest he considers pursuing it if increased protein doesn’t do the trick and he’s not satisfied with his quality of life.

Also, he might consider a day or two a week of less mild, more intense strength training.

Hi Mark,

I’m from Australia, I recently became a certified primal expert. I recently met a sheep and goat farmer from the Toowoomba region where I live and he was telling me about how he uses hydroponically grown sprouted barley as fodder for his livestock. Have you done any research on this method of feeding? How does this method of feeding stack up compared to grass feeding? I tried doing a bit of digging about sprouted barley as fodder but I couldn’t find anything that compared it to pasture feeding. I love your work and I hope one day I can attend PrimalCon or any other Primal/Paleo convention and have the opportunity to meet you in person. Thank you so much, you have enhanced my life



Luke, glad to have you aboard the cert program!

Pasture is generally superior to everything. That’s pretty much a given at this point. Sprouted grains are more grass-like than their seed-like un-sprouted counterparts, as a recent review concludes (PDF):

  • Vitamin content increases dramatically, particularly vitamin E and beta-carotene. If the fat’s yellow, that’s the carotene. More vitamin E increases the oxidative stability of the animal’s fat.
  • Enzyme activity increases, promoting greater micronutrient bioavailability (which, as you know, ends up in the meat).
  • Protein content increases. Animals need protein to be healthy and happy, and healthy/happy animals produce better meat.
  • Protein quality improves. Again, healthier animals are better for everyone.
  • Fiber content increases. Animals who eat a higher fiber diet have more conjugated linoleic acid (CLA) in their fat.
  • Essential fatty acids increase, especially the crucial omega-3s.
  • A study in livestock found that cattle fed sprouted barley experienced remarkable weight gain that coulnd’t be explained by the energy intake alone. That means more efficient feeding and, hopefully, lower prices for the consumer.

Plus, from my research, the Australian farmers (the pioneers in sprouted barley as fodder) using sprouted barley are doing it in the offseason when natural pasture is less available. They’re generally not using it to replace fresh grass, but to replace regular old grain feed. This is a big win in my book, and I’d love to try some sprouted barley-fed lamb and goat meat. Make sure that the animals are also receiving fresh pasture when available in addition to the sprouted barley. Let me know how it is!

Since you are always up to date on the research, I was surprised to see the omission of a recent study on pistachios and leaky gut in your discussion on nuts today:

Influence of Pistachios on Performance and Exercise-Induced Inflammation, Oxidative Stress, Immune Dysfunction, and Metabolite Shifts in Cyclists: A Randomized, Crossover Trial

Although the authors try to make the case that the increased intestinal permeability seen during exercise was the result of chronic pistachio ingestion, it isn’t clear based on their experimental design that it wasn’t an acute interaction between the pistachios and exercise. Either way, this is one of the best in vivo studies we have to date showing how foods can increase the permeability of the intestine and have negative cellular consequences.


This is an interesting paper. Thanks for sending it. If you guys want to read it yourselves, the full text is available in the link Eric provides, but here’s how it went down:

Trained cyclists were split into two groups. One group ate 3 ounces of pistachios every day for 2 weeks. The other group did not.

After two weeks, everyone showed up to the lab for a 75 km time trial on the stationary bike. The pistachio group ate another 3 ounces of pistachios before and during the trial. The other group drank only water. Both groups fasted overnight.

Time trial performance was 4.8% slower in the pistachio group.

The pistachio group showed elevated plasma levels of raffinose (a type of pistachio fiber), sucrose, and certain markers of oxidative stress. Both groups experienced exercise-induced leaky gut, as exercise leads to acute increases in intestinal permeability as a general rule. So it wasn’t the pistachios causing the leaky gut, although the pistachio group had unique stuff pass through the gut into the blood.

Okay, so what’s going on? Are pistachios bad for you?

They ate 3 ounces, almost 100 grams, of pistachios every day. That’s close to a half cup of nuts. I don’t recommend eating a half cup of nuts daily. The occasional nut binge? Sure, it happens. But daily? No.

They appeared to simply add the pistachios on top of their regular diet without replacing any calories. According to three-day meal records, pistachio eaters routinely ate 35% more calories than the no-pistachio group. 3 ounces of pistachios is 477 calories, or an extra medium-sized meal — comprised entirely of nuts.

One of the elevated markers of oxidative stress was 9,10-DiHOME. 9,10-DiHOME is a toxic metabolite of linoleic acid oxidation. In cell culture studies, 9,10-DiHOME causes mitochondrial dysfunction and increased oxidative stress to cells. It alters the inner membrane stability in mitochondria and increases the release of a protein involved in cell death. The pistachio eaters’ elevated post-exercise levels of lysolipids — lipids that form the mitochondrial membrane — may indicate 9,10-DiHOME-mediated disruption of the membranes. If the power plants of our cells and, ultimately, muscles, aren’t working well, our physical performance will be compromised.

Another marker of PUFA oxidation — azelaic acid — was also increased in the pistachio group.

So, are pistachios, and any other nut with moderate to high levels of linoleic acid, bad? At first glance, it certainly seems like it.

But consider that the pistachio eaters were also eating 35% more calories than the non-pistachio eaters. In other words, they were in a state of energy excess. And when linoleic acid contributes to caloric excess — when you start eating a half cup of pistachios on top of your normal diet without changing anything else — problems may arise. The toxin 9,10-DiHOME increases, potentially enough to start disrupting mitochondrial function. Markers of PUFA oxidation and subclinical atherosclerosis rise. That may have been what happened to the pistachio-eating cyclists, who ate 22 grams of linoleic acid to the water-drinkers’ 9 grams on top of their already-high calorie intake.

I suspect as long as you’re hypocaloric or eucaloric, linoleic acid from healthy sources won’t be a problem.

In the end, this study isn’t about pistachio-induced leaky gut. The leaky gut happened irrespective of pistachio intake. But it does reinforce the advice I always give to people wondering about nuts:

Nuts are snacks. Don’t make meals out of them.

Nuts aren’t “free calories.” If you can’t account for your nut intake by reducing food intake elsewhere, you shouldn’t be eating them.

That eating some nuts is good doesn’t imply eating more is better. It’s safe to assume that, like many things in life, nuts have an upside-down U-shaped dose-response curve. Where the peak of the U lies is up in the air, but it’s probably not at nearly 500 calories of pistachios every single day.

That’s it for this week, folks. Thanks for reading and be sure to chime in with your input down below!

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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34 thoughts on “Dear Mark: Preventing Age-Related Muscle Loss, Sprouted Barley-Fed Meat, and a Pistachio Downside”

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  1. Willpower has always been in short supply for me, and I don’t know how anyone can just eat a few macadamia nuts (the amount for a “snack”) and stop. It seems impossible. One more challenge to overcome.

    1. I totally understand. Nuts used to be very difficult for me too. With time I’ve learned now that when I want some nuts I can scoop up a handful, and by that I mean 6 to 10 nuts depending on variety (less if they are large), and if I eat them slowly that’s enough. They are nutrient powerhouses and should be treated as such but I agree it’s a struggle especially with something that tastes as amazing as macadamians.

      1. I measured how much a handful that I would spill if I turned my hand over was and its about 1/4 C. So I try to enjoy that and stop. Unless I’m eating nuts to avoid something REALLY tempting that is much worse for me.

        1. I think the pistachio study is the classic example of pretty useless information. All it does is push us all further towards eating disorders and an unhealthy relationship with food. Come on – eating 3 ounces of pistachios while riding a bike? What nut job conceived of that? I consciously ignore most of the stuff on MDA the simple reason that if I internalized and followed ALL studies and advice I would:

          1. Eat Nothing (everything at one point or another has a study that seems to be designed to accomplish nothing but to needlessly scare people)

          2. Do Nothing (if I followed ALL the exercise advice I’d basically walk really slow all day, quit my job because it requires too much sitting, and sprint a couple times a week. Goodby surfing everyday.)

          3. Get Nothing Done (too busy chasing down grass fed beef, spouting nuts, shopping for vegetables, filtering my water, and sleeping 8-10 hours per day)

          4. Obsess Over Carbs and Ruin Every Vacation (Have a panic attack whenever i had to go to a party or eat out – don’t want to shatter the 150 gram carb curve and suffer from insidious weight gain!)

          I love this site and read it regularly, but I see the effects of this 24/7 flow of isolated, very circumstantial studies have on people. Every day Mark has to talk someone off the edge of the cliff who’s freaking out about the two slices of pizza they just ate. Or reassure someone who’s thinking of quitting running, which they love and makes them feel great, because they fear the totally mythical and made up “chronic cardio”.

          Just because Mark does it, or says it, doesn’t not make it so. And he’s the first to say that. But the constant flow of scary tidbit of information will make you batty if you don’t ignore most of it.

    2. It’s easy to eat just a few macadamias for me. But, I’m not a huge fan of them. They’re okay, and I won’t say no to a couple.But more than that, no thanks. I know, that doesn’t help you any at all. If I figure out the secret to self control around chocolate for me, I’ll share. I’m sure that’ll be more helpful to you and macadamias.

  2. Vitamin D deficiency can also contribute to mucle loss in elderly person, according to (from 2002 and a lot of citing articles since then).

    Seems reasonable that it might be something there, given the interplay between cholesterol, vitamin D and testosteron.

  3. Regarding the barley fodder: I recently switched my hens to this in combination with the freedom to roam the yard and do their chicken thing. I made the decision for two reasons – first, the price of organic, high quality feed has skyrocketed to the point that it’s difficult to justify keeping the girls around for egg production, and second, I took a fodder class and just wanted to try it.

    So my chickens get a combination: they free range all day long, they get organic veggie scraps from the kitchen and garden, and they get a big wad of fodder in the evening when I put them to bed.

    The results have been incredible. I find it superior to giving them feed from the feed store. The girls are delighted to get their fodder each day, and the color of the yolks has darkened to a beautiful, rich orange color. It’s a rule of thumb that the darker the yolk, the more nutritious the egg is. (Grocery store eggs from factory farms are usually a very pale yellow.) I wish I had taken a before and after picture of the yolks!

      1. Yes. I buy a non-treated barley from the feed store and it takes about 5 days to turn a big scoop of it into a meal for 4 hungry chickens. I just use a couple of buckets per batch (one for the sprouts and one for catching drainage) and start a new batch each day. It only takes a few minutes and the return is amazing.

        1. That is good to know . Does the one bucket have holes in bottom for draining?

        2. Yes – there are really expensive sprouting systems out there, but I just use two food grade buckets to make a batch. I drilled lots of small drainage holes in the top bucket. You have to make sure the holes aren’t so big that your barley slips through.

  4. The best way to reverse (as opposed to slow) age-related muscle loss is to stop aging.

    1. A good one (-: Jokes aside, the only way to slow down the aging process is by being insulin sensitive, which in return slow cell division; something that MDA readers already know.

      1. Apparently the best way to slow cell division is calorie restriction, and eating low (but sufficient) protein.

    2. Sadly, as in all things, there’s a trade-off. You’ll either begin to age, and have all the issues that go along with it, or begin to decompose.

  5. I don’t think it takes two weeks of 1/2 cup of pistachios per day to adversely affect a cyclist.
    It only took one evening snack of pistachios the day before our ride. I have leaky gut issues anyway, and I now think I also have to pull nightshades out… however, the ride yesterday was HORRIBLE. I had such pain in my thigh muscles! I basically limped home. I did the same ride the previous weekend, with no problems.

    I don’t have great impulse control, so I have to be even more careful with portion sizes. I was really happy about the pistachios, but now I think I have to back them way, way down to few to none…

    1. I’ve recently started paying attention to the FODMAPS I’m eating and pistachios are a high FODMAP food. Could that have anything to do with your experience with them? I don’t know enough about the subject yet to say much, guess I’m asking more than anything here, and wondering.

      1. Yeah, I’m doing a stepped-elimination process as I’m trying to dial in my particular triggers.

        Too many pistachios have always been bad. Now, I’m wondering if ANY is too many… *sigh*

        Nightshades. Current eliminated items….

        1. I have been reading MDA for many years and was introduced to Mark through back in 2002. His show is about fungus and mycotoxins in the food supply. There are 2 nuts he suggests you leave out, these being pistachios and peanuts because of the mycotoxins. I am speaking of the Phase 1 diet.. I lean toward the Paleo side of it. Also the grains are contaminated leading to additional problems that are even beyond the carbs, giving more reasons to avoid them. I love Marks vitamins also, which I take every day.

  6. Let me give you a little inside information … It’s the goof of all time. Look but don’t touch. Touch, but don’t taste. Taste, don’t swallow. Ahaha – John Milton (Devil’s Advocate). Remember that quote? That’s what dietary advise (no pun intended) feels like at times. And based on the above, I might have exceeded my nut quota for the day (a hand full of Pistachios, 5/6 Macadamia nuts, 1.5 Brazil nuts and 2 walnuts. On the other hand and if I read you correctly, I might be alright as long as I don’t ‘t exceed my caloric intake. Especially, if it included lots of good fats (Pasture&organic eggs, coconut & grass fed butter) and omega 3. (-;

    P.S. Thanks for the Primal connection offer.

  7. On my way to T.J’s now and am taking pistachios off my shopping list. I have the last bit of the ‘cashew pieces’ in a bag. After I finish off that bag there will be no more nuts in my life. Or nut butters.

    1. you are crazy. I love pistacios. Because they tested slightly lower after consuming additional calories while riding bikes? Who cares.

      If they test wanted to me more accurate, the second group should have ate the same amount of calories at the same time, not eat nothing.

  8. Mark, I can vouch for the flavour of sprouted barley meats, I’d have to say I’ve found it superior to most other. Yes you are right, from what farmers have told me they either feed the sprouted barley on the off season or as an intensive feed 2 weeks prior to slaughter with grass only for the rest of the time.

    Flavour- wise I’d take it over any other, many top restaurants do too.. the consistency of the meat quality and flavour is exceptional and whatdraws the restaurant owners/ chefs that I know use it to it… and no I’m not a rep..

    Cheers for your ongoing dedication to information spreading .

  9. I am 66 and do not experience muscle loss. I eat about 100gm protein for my 154 lbs. I do HIIT exercise 2x week plus very heavy weights (405 leg press) 3x week. I started paleo living about 2 1/2 years ago, lost 22 lbs and then gained several pounds back in muscle. Loving it!

  10. In regards to Casey’s father, in addition to what you mentioned Mark, STRENGTH training also must be added! About 10 years ago I had an older client in his 60s and when he first came to me he told me all his injuries I filled up a whole sheet of paper with this data. He barely could squat his body weight when I first started working with him. In six weeks I increased his flexibility and strength tremendously. He was able to squat 175lbs for 10 reps with perfect form. He was also able to move infinitely better in his everyday busy life in New York. Therefore you got include STRENGTH training as part of your health proactivity! 🙂 My motto is “Super Strong, Vital, Ripped and Power”! I have been training clients and athletes to reach their peak health condition for over 14 years.

  11. With regard to sprouted grains, it seems to me that there may still be a problem with sustainability in the long term. Barley is more drought-resistant than wheat, which is a big plus. However, unless the grain is locally and sustainably grown, it could be environmentally costly.

  12. “Nuts aren’t “free calories.” If you can’t account for your nut intake by reducing food intake elsewhere, you shouldn’t be eating them.”

    That’s me, in a nutshell. All containers of nuts are to me the single serving size. So, I tend to avoid them. I’d rather have a steak.

  13. Mark,

    I’m experiencing a bit of cognitive dissonance with the eat more protein to help stave off muscle loss. While this recommendation makes loads of intuitive sense, it is counter to the idea that I need to moderate my protein intake to avoid gluconeogenesis thereby raising my blood sugar. Is this just a tightrope that needs to be walked, or a trade-off (muscle vs blood sugar)?

  14. what a flawed study.

    One eats something, the other eats nothing.

    Instead of blaming on eating SOMETHING vs nothing, they blame the type of food.

  15. Dear Mark,
    I find the information about dietary linoleic acid very confusing. How do you put together the above inflammatory effect of linoleic acid and last year’s meta analysis here:

    I understand your thoughts about hypocaloric and eucaloric consumption of linoleic acid but the above makes a dose response claim for the inverse relationship of intake to cardiovascular disease. Any comments?