High fructose corn syrup.

My vote goes for gluten with PUFA's running a close second. At least that is the order that they punish me in.

I think it might vary by individual.

The biggest offender imo is hydrogenated oil, with trans fat being the worst.

PUFA because there is no upside. A fresh-baked loaf of bread can be heavenly. We can get pleasure from a sweet treat. But what is the upside of PUFAs???? People lose their health so they can eat disgusting margarine and GMO soybean oil??? EPIC FAIL

My feelings right now are:

1. Gluten
2. PUFAs
3. Sugar

You can get the unholy trinity by eating a donut.

This may sound like a flippant answer, but I would say that the one ingredient (or factor) which leads to the most problems in the modern world is convenience.

PUFA trans-fat and sugar. I don't think traditionally prepared wheat in normal quantities is a huge problem for some populations. It's worse for others of course. But industrial oils and sugar aren't good for anyone.

I was born in 1983 and hadn't tasted real butter until recently. I shudder at the thought of all the tubs of margarine I ate, all the hydrogenated soybean oil mayo and hydrogenated peanut butter. Every day I had gobs of all three. When I was 22 I had an ekg, ultrasound and heart monitor because I had a heart murmur and chest pain (docs concluded it was fine, but it still freaked me and my mom out).

Millions of people like my parents raised their kids on the stuff thinking they were doing the best for their health. And its the reason why I will never support any government "healthy eating" efforts, even if I ultimately agree, like the soda tax. I am of Mexican and Native American ancestry and I want to scream when I think about how many of my relatives, friends and community members have had their lives cut short as a direct result of the government meddling/guidelines. Just about everyone in my family over age 40 has diabetes and many younger ones as well.

Great question! My vote is for yellow #6, which makes Mountain Dew harmful. But for real, I'm betting against gluten, and putting money on either PUFA or sugar. Gluten can be terrible for some, can creep up on others as they age, and can seem to have no clinical effect on others. PUFA affects the body's hormonal milieu, and sugar does nothing good and is addictive as crack. I'm eating a bar of 86% chocolate right now and I have to use all my willpower to keep some for tomorrow.

High Fructose Wheat Gluten

You know somebody out there is going to invent it, just to put it in Corn Sugar Smack(s) Cereal.. now with Sweet Soy Milk.

From what I have read, the "diseases of civilization" really ramped up when sugar became available to the masses. Rich men's diseases like gout and obesity became common after the 1700s saw sugar prices drop to the point where it became more than a rare treat for most people.

It's hard to overconsume sugar in its natural state (in fruit or even in the cane), but once refined, it is a scourge.

Gluten, I think the science shows that nearly everyone has a response to it.

http://wholehealthsource.blogspot.com/2008/12/gluten-sensitivity-celiac-disease-is.html

Sugar, though harmful, isn't the biggest worry in my opinion. Refined sugar is definitely a source of trouble, but there are are hunter-gatherer populations that get nearly all of their energy from carbs and still don't suffer from the diseases we do. So there HAS to be something else going on there.

The skewed omega-3/omega-6 balance is a pretty big deal as well, I might put that second.

[Edit] I think a lot of it has to do with the combined damage from damaging substances (gluten, lectins, trypsin inhibitors, etc) on our gut and body and that it has made us much more susceptible to the effects of these damaging substances. It's basically the perfect storm of chronic disease.

My vote goes to vegetarianism. After reading "The Vegetarian Myth" by Lierre Kieth, I want to eat them all. I loves me some grass fed/grass smoked hippy. Veg Heads are as Neolithic as you get. No Paleo tribes surviving on plants. I don't worry about the souless money chasing men and women who sell us grains and sugars and oils. They will move on to greener pastures when they are shown the money trail. But...the holier than thou Vegers who claim moral high ground have great access to the media and influence. The insulin I inject every day to keep me alive exists because dogs were sacrificed to perfect the insulin techniques. I love dogs but I love Diabetics more. I can avoid the grains and sugars and seed oil obstacle course but the Vegetarian Agenda makers want to shove a carrot down my throat. Gag. This town ain't big enough for the both of us.

Gluten, PUFA then sugar if we're talking relative concentrations.

Gluten exerts it's effect at very low concentrations (nanomolar).

PUFA exerts it's effects at the single digit gram level (4% calories as n-6 is a nasty level).

Taubes had a section ball parking sugar's effects at around 20 grams a day in indigenous cultures.

i'd say any undiagnosed food allergy in general. you can eat perfectly healthy, but they still can make you suffer for decades, without you even knowing why. EVERY chronic problem you have, e.g. knee pain or skin problems etc should be challenged with an elimination diet to see if it's caused by an allergy/sensitivity. for example, i had worsening knee problems (similar to arthritis), and only recently found out it's actually from milk protein. even butter is enough to trigger it for me.

PUFAs.

A good number of primitive cultures eat/ate grains without any diseases of civilization. Most did some kind of preperation (fermentation, soaking, etc), but not all.

Perhaps PUFAs and sugars jack up our guts and induce gluten sensitivity.

I'm leaning more towards sugar than gluten. It's probably not helpful to make the distinction. But fructose at current rates of consumption is drastically hampering the bodies ability to detoxify itself. I wouldn't at all be surprised to find fructose as the major factor in metabolic derangement.

Per usual, Sugar the Bitter Truth: http://www.youtube.com/watch?v=dBnniua6-oM

The question a lot of people seem to be answering is what's the better binge: Sugar, PUFAs, or gluten. Sugar is the better binge because of the level of dosage it takes for problems to arise. But looking at the current levels of consumption, I'd say more benefit would come for removing sugar than removing the other two. But really we don't know is the answer. All of them suck.

What about genetically modified foods? Then fructose and gluten. Then all the other crap.

I think its PUFA or sugar...which one, though? Tough.

If sugar includes HFCS then i'd say thats gotta take it. Even within my own time on this planet (31 years old) I've seen, and been subject to, the ill effects of the massive change in sugars' presence in the SAD. Sure, my diet growing up was never good (by what i now believe) but nearly every year it seems there is just more and more sugar in the SAD.

I'm with PUFAs. It's possible to get obesity and diabetes without gluten, but I bet it would be super tough to do without Out of balance PUFAs

I am a celiac so grains/gluten and dairy are a tie for the number one spot. I react badly to both!

Either

A: transfats, since no human has the pathways to make good use of those altered fats,

or,

B: whichever neolethal ingredient you are highly allergic to...

Example: transfats will make me obese and unhappy/demented, but red-40 will kill me quick.

I would say that the most neolethal food would be the one that leads to eating even more neolethal foods! Probably sugar...

many people that post here and throughout the paleo/primal community have some serious misunderstandings related to PUFAs. Omega-6? it's an essential fatty acid. you NEED it, folks. too much is bad, and it's easily acquired, but to count it or any other PUFA as a neolithic food ingredient is really just wrong. PUFAs are found in meat too, so they're by definition paleolithic. and Omega-3, which we all love, is a PUFA.

i think i know the basic context in which you've offered them up as a neolithic ingredient - added oils like sunflower, corn oil etc. agreed on my end, those are no good.

but the way that people speak about PUFAs in our community would make a scientist laugh.

What is the worst possible neolethal ingredient?

First: any Partially Hydrogenated 'Vegetable' Oil

Second: High Fructose Corn Syrup

Hydrolized Corn Gluten. I saw this listen on some mauana loa macadamia nuts. It just sounds evil.