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Giving Thanks to Your Low-Carb Ancestors: A Recipe for Brain Health

A lot of folks keen on losing weight have been convinced that a diet low in fat and protein and high in carbohydrates is the way to go. Seems intuitive, doesn’t it?: Don’t eat fat and you won’t get fat. That’s why, odds are, this year someone at your Thanksgiving table will be giving thanks without giving your perfectly browned holiday turkey a second look. Instead they’ll be opting to load their plate with their favorite high-carb “health foods”—sweet potatoes, stuffing, and cranberry sauce.

Grain-fed turkeys gain weight faster but have significantly smaller brain size than their omnivorous wild cousins of the same breed.

If you’re a regular reader of my blogs, you already know what I think of high-carb diets as a means for losing weight: I’m not a fan. But today, I’d like to skip the weight loss discussion and, instead, focus on some of the unintended health consequences of cutting healthy fats and proteins from your diet.

It’s Thanksgiving, so let me bring your attention to a study that came out a few years ago that focused on turkeys. According to the study, turkeys fattened up on an all-grain diet were found to have brains that had failed to grow normally: The all-grain turkey brains weighed in at slightly over two-thirds the weight of the brains of turkeys in the wild—turkeys with full access to the bugs, worms, and small lizards typical of a turkey’s natural omnivorous diet.

That’s right, I said “omnivorous diet.” If you were fortunate enough to catch the recently aired PBS documentary “My Life as a Turkey,” you know that wild turkeys are complex and highly social creatures who hunt and poke, in addition to seeds and grasses and tiny sprouts, for all manner of creepy crawly things—caterpillars, worms, and shiny green grasshoppers, to name a few.

To a family in their Volvo driving by an open field filled with wild turkeys, the birds appear as a head-bobbing coterie of gentle grazers sunbathing and promenading through windswept grass. To a grasshopper clinging to the end of one of those grassy stalks, however, those same birds represent a fast approaching phalanx of razor-beaked predators. Grasshoppers know, intuitively, what we often forget: Turkeys are, after all, meat eaters, and they are voracious.

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Which brings us back to the turkey study: An unnatural, all-grain diet winds up gobbling up nearly a third of a turkey’s total brain mass. So given that turkeys are omnivores, might these omnivores have something to teach us about the health of other omnivores, like humans, placed on an unnatural low-protein, low-fat diet?

Could we be putting our own brain health at risk by adhering to a low-fat, high-carbohydrate diet?

After decades of clinical experience, I would have to answer yes. Like our omnivorous feathered friends, our brains need the requisite nutrition to grow, develop, and function properly. Therefore, people may be placing their health at some peril when they choose to deprive their bodies of the full spectrum of natural proteins and fats. It’s no wonder, then that as a result of cutting fats and cholesterol (15% of your brain’s weight comes from cholesterol) many people find themselves dealing with memory deficits, or metal fog or depression. (Results may vary depending on your unique metabolic patterns.)

What should we take from from all this? First, a Thanksgiving turkey raised humanely—in a natural, open-air environment with free access to forage—is a lovely thing. But it ain’t cheap; that’s why the price sticker on a free-range turkey can make your jaw drop. If you discover such a free-range turkey, properly prepared, on your table, it’s definitely something worth giving thanks for, first to the bird, then to the farmer, and then to whomever and whatever else you feel deserves your thanks. It is, at once, a sacrifice and a blessing.

A traditionally-cooked, lovingly prepared Thanksgiving dinner (with a good glass of wine) is one of the most soulful and healthful things we do all year. Should we embrace it, or feel guilty about it?

As far as this doctor is concerned, that’s a no-brainer.

Happy Thanksgiving, everybody!

With over two decades of clinical experience and expertise in genetic and biochemical research, Dr. Cate can help you to reverse metabolic disease and reshape your body.

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This Post Has 16 Comments

  1. Ketosis is simply the metabolic state by which we can measure that you are burning fat, which is the healthier fuel. So to answer the question, ketosis is a good thing! Carbs are not as ‘clean’ a fuel as fat, and many of our systems run better when we are in ketosis at least a chunk of the time. My New Years post will be related, as I will explain why fat burning is key to weight loss.

  2. Hi Dr. Cate. Got your book from amazon–just scanned, have not read it yet.

    What are your thoughts on ketosis? A pure paleo diet tends to be low carb and moves us toward ketosis. Do you see ketosis as positive, something to achieve, negative, something to avoid or does ketosis not matter?

  3. The research compared birds of the same species but with differences in their living conditions/diet. I’m not sure that a restricted environment would influence brain size. After all, it doesn’t influence bone size…They grow just as big. But its a good question, especially as it applies to lab animals, domesticated animals, and us humans: Does a monotonous environment actually shrink brain size?

  4. Regarding the study, I only read the abstract but it looks like they compared wild vs domestic turkeys. In that case, the difference in brain size would be accounted for by the bird’s interaction with its environment rather than the diet alone, right??

  5. Hi Tina,
    Glad it’s working, so fart. Oops , type-o, but a good segue…
    I agree w/ your lactation specialist. The alkaloids in plants are fat soluble and could theoretically be secreted into breastmilk, since fat-soluble drugs can be, and so it makes sense that they could potentially cause issues w/ baby’s GI tract.
    For bone broth, you might want to explore the wonderful world of sauces. Veloute sauce in particular can be broth based. Iv’e recently discovered . They’ve got awesome videos. They’re by subscription, but inexpensive, culinary school quality and to me they save time searching through not-so clear presentations on you tube. Plus, if you join for even just a month, you get to ask the culinary artists questions and they answer back real quick!

  6. Yes, a thousand times yes. I spent a long time eating a low-fat vegetarian diet, and I have no doubt it had serious consequences for my brain and body, I just didn’t see them coming until they crashed on me all at once. And I don’t think I fully believed it until I changed my diet and then suddenly felt better — happier, more energetic, more like myself. I don’t think people understand enough the role of dietary fats and cholesterol in proper brain health. People are far too focused on the way diet affects one’s physique, and how that affects one’s sense of well-being. A poor diet can short circuit the psychology and go straight for the brain.

  7. Thanks Dr. Cate! I’m very committed to eating the best I can while nursing. Last week, I seemed to grab a bit too much fruit, and I think you’re right – when I was pregnant I could get away with eating more fruit (especially sweet ones like bananas), and now it’s affecting me more. Yesterday, I didn’t eat any fruit, except an apple and I felt much better throughout the day. I also upped my fat (put more butter on my eggs) and olive oil and avocado in my salad, and that seemed to help. By the way, do you believe in gassy foods causing gas in newborns that are breastfed? Our pediatrician says it’s a myth, as breastmilk is made from the blood of the mother and gas doesn’t go into the blood. However, my lactation consultant said I should watch with eating too many vegetables and salads. I lived on salads while pregnant, so I’m curious as to your opinion. Thanks again! OH, and any ideas what to do with the bone broth made from the turkey carcass leftovers from Thanksgiving? I have so much made – going to use most of it for soup, but wanted to think of other ways to use it.

  8. Cate, let me take this one.

    Hi Jim,

    Surely you don’t really think anyone’s suggesting vegetarians’ brains are deficient. I mean, honestly, how could you come up with that? If your question was just sort of a lark, then may I ask, Can we please agree not even to engage in such nonsense? We’re at the grownup table now, and no one at this table has the time, the energy, or the disposition to….You know what? Life is short; what do you say we just skip ahead to your more serious comment, about the lacto-vegetarians.

    Cate will correct me if I’m off base here. It’s not just a matter of harm from grains, or simply a matter of a deficiency of nervous system nutrients. It’s both, together. Taking away a portion of a turkey’s omnivorous diet is unhealthy for the bird. Replacing it with a bunch of grain is unhealthy for the bird. Naturally, taking away the one and replacing it with the other means the turkey’s going to be in double trouble, just in the same way that its omnivorous human distant cousins would be in double trouble. It doesn’t kill the turkey outright; it just shrinks its brain, inhibits full-fledged physiologic expression, and makes the bird less healthy overall.

    If vegans retain the dairy and egg portion of their omnivorous diet, that’s going to help them out. Save for the glycosaminoglycan group of nutrients, they’ll still be getting just about everything they would get from eating meat products. So, to answer your question, including these healthy nutrients would be beneficial to someone intent on eating a lot of grains.

    As you mention, lots of smart folks choose want to avoid supporting the cheap meat industry, and for darn good reason. Part of the reason they’re able to consider such ethical questions is that they’re smart enough to wrangle with difficult ethical problems. And one of the reasons they’re smart enough is because their brains developed normally as babies and children. And for that they have their omnivorous parents and grandparents and great-grandparents to thank, their ancestors who took in the nutrients necessary for a healthy genome and for the formation of a physiologically advantaged child.

    It’s now become a cliche, the vegan physician author/speaker whose working brain, good looks, athletic stature, and enviable health are all the products of his family’s traditional omnivorous dietary history decrying the very foods that delivered those physiologic gifts. They talk about the small family farm of their childhoods as though they were some kind of marginally forgivable sin, the privacy and access to nature they enjoyed—something now experience by few except the extremely wealthy—painted as some kind of regrettable anachronism as opposed to a luxury and privilege of the first order.

    No, I don’t believe the traditional family farm is the product of some error of consciousness. It’s a good thing. One of the things it does for kids, in addition to giving them that amazing anatomy and health, is to teach them about nature, the connection and love for animals, the cycles of life and death. These kids live among animals they care deeply for and learn that they feel, get lonely, anxious, and excited, that they make friends and enemies, and all the rest. And they question, as they should, whether or not people should have the right to eat such intelligent, social creatures.

    Which brings us back to your intelligent vegan friends. They’re right to keep asking that very question—should we eat animals?—and to ask us to ask that question, just as you are right to do so. But it so happens the overwhelming bulk of scientific evidence tells us that, due to our evolutionary past, human beings still require animal products of various kinds to maintain proper weight, repair connective and nervous tissue, and make healthy, physiologically sound offspring. Vegans are right to suggest that eating steak, for example, just for the taste is to indulge in entertainment at great (ethical) cost. But we need to remember, there is a reason that grass-fed steak tastes so good—because our bodies (this applies doubly so if you’re pregnant) cry out for it. It’s way beyond entertainment. It’s as essential and—I mean this word in the non-dietary sense—primal as it gets.

    Jim, the science says that humans are still omnivores, and that our health benefits by recognizing this. But everything that MAKES us human tells us that we must do everything in our power to maintain healthy eating traditions while at the same time loving and celebrating animals, all animals, including those whose bodies will, in time, conjoin with our own in the form of a meal.

    In today’s modern, crowded, overstressed world, this strikes me as a near-impossible feat. And when a vegan asks, “How they heck can you love something and also kill and eat it?” I understand the grammar of the question. It can’t be done easily. We’re not talking about a drive-through experience. And I’d be lying if I were to say that maintaining a healthy traditional diet with humanity and care isn’t becoming increasingly difficult. It is. Trust me. I’m appreciating this fact more every day. But that doesn’t mean we can’t start walking toward that goal, together, armed with the pragmatism of nutritional scientists and the consciousness, and conscience, of vegans.

    Vegans and meat eaters together need to fish this discussion from of the oily muck of the blogosphere and clean it up. What we’ve got here isn’t a failure to communicate. What we’ve got, between vegans and traditionalists, is a failure to sit down together, at the grownup table, and talk turkey (sorry about that. It’s Thanksgiving, after all).

    There’s now well over 7 billion people on the planet, and they’re all hungry. How can we do what’s right for animals and for the earth while at the same time facilitating the best possible health for ourselves and our children. That’s a serious question, and that discussion’s going to need the input from every corner, including you and your smart vegan friends.

    So what do you say, Jim? Do you want to help us figure this thing out?


  9. What about the many vegetarians who eat diets with lots of grains? Are you saying that their brains are deficient?

    I know some very smart lacto-vegetarians. Is the “lacto” (milk, cheese, yogurt) part of the diet sufficient to offset any harm from the grains?

  10. Tina
    If you are hungrier now, perhaps your high estrogen levels during pregnancy was suppressing a little bit of insulin resistance that is now unmasked an causing sugar level swings. If you are feeling hungry after 3-4 hours without starchy foods, you may be getting hypoglycemic. See if you follow the pattern on this graph posted at the bottom of the page here:

    You may want to get thyroid levels tested as well and a good thorough exam.

    It is possible that yourre just making super high-quality milk and need to eat more overall.

    For most people low carb should not affect your milk supply, however everyone is different.
    If its just a general sense of hunger all the time, not related to potential blood sugar lows, then as long as you are eating plenty of protein-rich foods, bone broths, lots of good fats and fresh veggies, go ahead and add starchy foods other than grains, ie rice or potato or fruit. See how you feel after 100-150 gm per day.

  11. Dr. Cate, I had my baby and now am
    Nursing. Just wondering if eating low carb mostly will effect my milk supply. I really feel terrible when I eat grains but I keep feeling so hungry when I don’t eat more starchy foods! I definitely wasnt this hungry pregnant. Thanks again!

  12. Kay
    Take a deep breath! You’ll have your answers … as long as you keep looking. It’s a lot to learn, made worse by the reality that we spend so much time in school learning things that have nothing to do with living a healthy life. You can keep reading online or you can buy a few good books.

    Here’s a quote from my favorite book (Deep Nutrition) to begin to be able to reason through the answer to kind of question you just asked:

    “If you want to know whether or not a steak, or a fish, or a carrot [or a potato] is good for you, ask yourself what portions of the natural world it represents, and whether or not the bulk of that information remains intact. This requires traveling backwards down the food chain, step by step, until you reach the ground or the sea.”

  13. one more time. I get it. Eat natural foods. Organic Butter. Good or Bad?? How much??
    Organic MIlk Good or Bad??? How Much??? Squash..Is it really a Bad food??? Potatoes??Bad for you??? Cured Pork??? a Bad thing??? How much animal fat is good for you???? How many Carbs per day in a healty diet??? How does a person “eat healthy” and “loose the belly fat????

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