Friday, November 29, 2019

Retrospective #286: Avoid wheat, excess fructose and excess linoleic acid (Omega 6s)

Kurt G. Harris, MD, called wheat, excess fructose and excess linoleic acid the Neolithic Agents of Disease (NAD). He was, easily, the early favorite in my search for a dietary regimen that could be stated as a philosophy of eating rather than depending on counting calories, carbs and other macronutrients. I first wrote about him nine years ago in The Nutrition Debate #19. He then dropped out of “the nutrition debate” and later deleted his Archevore website. Today he is a diagnostic radiologist practicing in Sturgeon Bay, WI. Some of his writing is still online at Psychology Today.
Harris didn’t write for Type 2 diabetics like me. He aimed his program at people who wanted to eat in a healthy way to avoid the chronic diseases of modern civilization. Others followed him in this goal and the field became a tangled mess, leading sadly I suspect to his premature retreat. For awhile I hoped he was writing a book. Alas, it seems not.
Harris was inspired by Gary Taubes. His training in scientific method fed his inquiring mind and led to his epiphany. He liked to write and coin words too. If this sounds like a eulogy, it’s only because I fear he is lost to us, and it is our loss.
The three NADs, which he explained in “A Dietary Manifesto – Paleo 2.0,” are just another way of describing his 12-step program (which I list in The Nutrition Debate #19), for “getting started” and going “as far as you can down the list…” The wheat proscription means gluten, and includes the other gluten grains (barley, rye, etc). That’s big.
The excess fructose NAD is also big, but here Harris leaves a little room if you’re not diabetic or prediabetic. Harris is infamous (in Paleo circles) for calling apples “bags of sugar” and most modern fruit “candy bars on a tree.” He concludes, however, “If you are not trying to lose fat [or are carb intolerant as in type 2 diabetes], a few pieces of fruit a day are fine.” Fructose, however, is not only found in fruit. Take a look at “Retrospective #97” for a list of fruits and vegetables and common sweeteners that contain fructose.
Avoiding excess linoleic acid (Omega 6s) is perhaps the hardest dietary goal of the three NADs because it is so hard to know where they hide. Harris advises, “The way to correct the modern excess of n-6 linoleic acid is to avoid the modern sources of it. Stop eating all temperate vegetable oils and veggie oil fried food – cooking and frying oils like corn, soy, canola, and flax, all of it. And go easy on the nuts and factory chicken. These are big sources of n-6, especially the nuts and nut oils.
All fats are combinations of saturated fatty acids (SFAs), monounsaturated fatty acids and polyunsaturated fatty acids (PUFAs), but the combinations vary enormously. Corn and soybean oil are over 50% PUFA, while butter and coconut oil are just 3% and 1.8%. Corn and soybean oil have more than 20 times as many PUFAs as butter and coconut oil.
The ratio of n-6 to n-3 is also important, and corn oil easily has the worst ratio. But in terms of absolute numbers, the best advice is to avoid excess Omega 6s altogether, and that is best done by eliminating all seed and vegetable oils.
To put some “meat” on the PUFA/n-6 advice, I’ve created this table using the USDA’s National Nutrient Database:
Cooking/salad oils & fats (%)
SFA
Mono
PUFA
n-6
n-3
n6/n3
Corn oil
12.9
27.6
54.7
53.2
1.2
45.8
Soybean oil
15.7
22.8
57.4
50.4
6.8
7.4
Canola oil
7.4
63.3
28.1
18.6
9.1
2.0
Olive oil
13.8
73.0
10.5
9.8
0.8
12.8
Butter (incl.+/-16% water)
51.4
21.0
3.0
2.2
0.3
6.9
Coconut oil
85.5
5.8
1.8
1.8
0
So, avoid using all vegetable and seed oils (corn, soybean, Canola, sunflower, walnut, etc.), and then avoid all prepared, baked goods and foods fried in any of these oils. Then go easy on nuts, nut oils and factory chicken, and maybe supplement with Omega 3 fish oils to improve the n6/n3 ratio, and you should get back into pre-Neolithic proportions. If this sounds like Paleo to you, it really isn’t. It’s just a nod to the “ancestral” roots of my dietary journey.

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