For today’s edition of Dear Mark, I’m answering two questions from readers. First, is it possible to become deficient in omega-6 fats as an adult? What would that even look like, and is there anything that might make omega-6 more important?
Second is a question related to last week’s feature on prostate health. Is saw palmetto an effective supplement for prostate issues? It depends on the issue.
I have a question for “Dear Mark”
Here it is:
I am completely and totally primal for 10 years now. Can I become O6 deficient ? Since 90% of my fat intake is saturated or O3.
It’s technically possible to become deficient in omega-6 fatty acids. The early rat studies that discovered the essentiality of Omega-6s found that their complete removal made the subjects consume more food (without gaining weight), drink more water (without peeing more than rats on a normal diet), develop scaly skin, lose fur, urinate blood, go infertile, grow weird tails, and die early. All this despite eating an otherwise nutrient-dense diet with all the fat-soluble vitamins (they even removed the fat from cod liver oil and gave the vitamins), B vitamins, and other nutrients a rat could ever want. The only thing missing was a source of omega-6 fats.
Once they discovered the issue—a lack of omega-6—how’d they fix it?
Coconut oil didn’t work, for obvious reasons. It’s almost pure saturated fat.
Butter worked, but you had to use a lot. The omega-6 fraction of butter is quite low.
Cod liver oil worked, but it didn’t fully cure the deficiency disease.
Lard worked well, as did corn oil, liver, flax oil, and olive oil. All of those fat sources fully resolved the issue and eliminated the symptoms. They were all good to decent sources of omega-6 fatty acids.
They also tried pure linoleic acid (the shorter-chained omega-6 PUFA found in nuts and seeds and the animals that eat them) and arachidonic acid (the long-chain omega-6 PUFA found in animal foods). Both worked, but AA worked best.
Throughout all these trials, exactly how much omega-6 fat did the rats require in their diets to cure deficiency symptoms?
When they used lard to cure it, the rats got 0.4% of calories from omega-6 PUFA. If the numbers hold true for humans, and you’re eating 2500 calories a day, that’s just 10 calories of omega-6, or about a gram and a half of pure arachidonic acid to avoid deficiency.
When they used liver to cure it, the rats got 0.1% of calories from omega-6 PUFA. If the numbers hold true for humans, and you’re eating 2500 calories a day, that’s just 2.5 calories of omega-6, or about a third of a gram of arachidonic acid to avoid deficiency.
The truth is that omega-6 deficiency is extremely hard to produce, even when you’re trying your hardest. Way back in the 1930s, the early omega-6 researchers tried to induce deficiency in an adult by giving him a 2 grams fat/day diet for months. Nearly all fat was removed, particularly the omega-6 fats, and the rest of the diet was fat-free milk, fat-free cottage cheese, orange juice, potato starch, sugar, and a vitamin/mineral supplement. Maybe not the ideal Primal diet, but better than some.
He ended up improving his health, not hurting it. There was no sign of deficiency.
Omega-6 fats are everywhere in the food environment, even if you’re actively avoiding concentrated sources of them. No one is developing a deficiency these days. However, certain conditions might increase the tolerable or beneficial upper limits of omega-6 intake.
If you’re strength training with the intent to gain lean mass, a little extra arachidonic acid can improve your results. The dose used was 1.5 grams per day. Average intake through food runs about 250-500 mg, though Primal eaters heavy on the animal foods are probably eating more.
If you’re recovering from injury or healing a wound, a little extra arachidonic acid can speed it up. AA is an important co-factor in the inflammatory response necessary for tissue healing.
Well done, Mark. My doc just prescribed saw palmetto to reduce multiple nighttime visits to the bathroom, though the research I’m looking at says there’s no clinical evidence to support saw palmetto for prostate problems. Your take?
It depends on the problem.
Large observational trials have found no connection between saw palmetto supplementation and prostate cancer risk. It neither helps nor harms.
Saw palmetto does seem to help benign prostatic hyperplasia, a non-cancerous growth of the prostate. This won’t cause serious health issues directly, but it can impede the flow of urine and lead to multiple nighttime bathroom visits. Saw palmetto is quite effective at reducing nighttime urination. If that’s what your doc is trying to help, I’d say give it a shot.
You might ask about combining saw palmetto with astaxanthin. It’s been shown to reduce the conversion of testosterone into estradiol that can sometimes result from plain old saw palmetto supplementation.
That’s it for today, folks. Take care and be well. Chime in down below if you have any questions or comments.
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.