Highly recommend the documentary "Forks over Knives."
Quite scientific and informative, though can be dry and overwhelming to the uninitiated.
Yooper, sorry to bring this up again, but I don't believe wheat is so much to blame in the big picture. Which is not to say they have no part in the blame! I have done quite a bit of research the past few days on this topic and wanted to share what I have been reading if anyone finds it of value.
I think the prevalence of processed corn in our diet, directly or otherwise, is a factor that is a bigger problem than grain, simply because we consume more of its refined product. It's not the sole problem for sure, but its in just about everything we eat. High fructose corn syrup, devoid of nutrients except empty calories, corn in chips, corn-fed beef (which makes the meat itself have much higher saturated fat content and serious health problems for the cow --
http://www.livestrong.com/article/529194-nutrition-of-grass-fed-beef-vs-corn-fed-beef/) which also makes our milk, corn fed chicken and everything really. Its unhealthy for cows and increases the amount of fat in the meat over traditionally grass-fed cows. Just look in the pantry and see what has processed corn in it!
http://articles.cnn.com/2007-09-22/...refiners-association-soybean-oil?_s=PM:HEALTH
http://abcnews.go.com/GMA/OnCall/story?id=4439943&page=1#.UISasYabHRs
Now kids can get soda, chips, and candy in schools and often prefer these to school lunches, which are usually not healthy either and largely are corn based. It is cheaper to feed kids high-density corn-based products because they are subsidized, while healthy foods like fresh fruits and vegetables are not.
http://pediatrics.aappublications.org/content/130/3/437
Interestingly, the current generation of kids might actually expected to live less than the previous generation for the first time in american history due to the effects of American diet.
http://www.georgiahealthnews.com/2012/05/largely-preventable-health-conditions-hamper-u-s/
Most food in America is corn. Almost everything in grocery stores has processed corn, and has an extremely high calorie density. Most important is calorie density because you can eat much less of it to get the same caloric value of, say, broccoli. Which means your stomach doesn't perceive being full nearly as fast. Stomach stretch receptors are a key pathway in signaling your brainstem that you are full and should stop eating.
http://freshfru.it/post/27596382690/when-our-stomachs-are-full-with-fruits-and-plant
Consumption of calorie-dense foods also means the pancreas secretes insulin in "peaky" intervals, then disappears quickly. Or it stays high altogether, along with glucose levels. This has been strongly implicated to cause insulin resistance, a key part of metabolic syndrome and later type II diabetes.
http://www.mayoclinic.com/health/glycemic-index-diet/MY00770
http://www.longactinginsulin.com/index.php/tag/insulin-spike/
http://www.examiner.com/slideshow/glycaemic-index-of-rice-varieties
http://www.life-enhancement.com/magazine/article/1877-glycemic-control-best-for-weight-loss (see section about glucose and insulin spikes)
Needless to say, consuming more empty calories in calorie density foods means more fat storage.
Heck, the corn grown in the grain belt is completely unpalatable unless highly processed! It's sometimes not even profitable to grow corn without government subsidies. I understand this goes back to food policy back in the 1970s (and of course before) where the government fiscally encouraged the amount of food yield based on subsidies. This allows companies to make corn-based products, which are nutritionally deficient and calorie dense, on the cheap relative to healthy foods.
http://www.calpirgstudents.org/medi...port-junk-food-instead-fresh-food-report-says
http://www.foodsafetynews.com/2011/09/ag-subsidies-fund-junk-food-report-says/
http://en.wikipedia.org/wiki/Earl_Butz#Secretary_of_Agriculture
My opinion is that the serious problems in health we are seeing (higher cancer rates, morbid obesity, diabetes type II, HTN, etc etc..) are from the unrestrained consumption of high calorie density foods - the consumption of which causes "peaky" insulin spikes, or simply persistently high levels of glucose which insulin everntually fails to manage, and does not stimulate the brain telling it that it is full - and the lack of physical activity. Americans like things fast, cheap, and easy. It's all of these to stop at McDonald's and grab an extra large #1 with a coke than it is to prepare a meal of vegetables, fruits, and legumes. Speaking of which, the meal is almost all highly processed corn and meat. The beef is corn fed, the milk comes from corn-fed cows, the soda contains largely high-fructose corn syrup, and the fries are fried in highly processed corn oil (or rapeseed or soy).
http://www.ecoliteracy.org/essays/we-are-what-we-eat
http://www.lifechek.com/webimages/obesity_cancer.gif
http://www.cutthewaist.com/impact.html
In addition, the consumption of these highly energy dense foods also increases the amount of inflammation in the body, measured commonly as CRP (C- Reactive Protein), amongst other things. It has been proven that diets high in saturated fats and energy dense foods causes a dramatic increase in CRP levels.
http://care.diabetesjournals.org/content/28/5/1211.full
http://www.medicinenet.com/script/main/art.asp?articlekey=46339
These inflammatory processes are how atherosclerosis forms, measured by CRP. Specifically, LDL cholesterol is not easily removed from the blood by the liver. This means it spends high amounts of time in the blood, and it has a higher chance of becoming oxidized, which is a very harmful process. Oxidants damage vessel endothelia, and cause migration of inflammatory cells to the area by signal molecules (cytokines) released by the endothelium. These proliferate over the indigestible oxidized LDLs eaten up by macrophages, which become foam cells, and attract platelets to form over them. This mass then narrows the artery. If the fibrous platelet cap is thin, the plaque is easy to break apart and may cause strokes. If thick, it can cause things like angina (chest pain) during exercise and pain in the lower legs when walking.
http://www.ncbi.nlm.nih.gov/pubmed/11795267
http://circ.ahajournals.org/content/91/9/2488.full
http://www.medscape.org/viewarticle/545748 (esp. third slide picture)
http://cmbi.bjmu.edu.cn/www-learn/labmeeting/labmeeting_014.pdf
http://www.angiologist.com/wp-content/uploads/2010/04/eng_atherosclerosis.jpg
TLDR; Consumption of energy-dense foods and lack of exercise are the problems here. They cause countless morbid, fatal, and extremely expensive diseases. Since corn is so prevalent in everything, is extremely cheap due to subsidies, and must be processed into calorie-dense forms it is the main culprit. We can debate the percentages of fats/carbs/proteins, but I think the basic message is eat more unprocessed foods like fruits and vegetables, and exercise.
I'm sure there are some errors here and that I left a good deal out, like the exercise (or lack thereof) side of the equation. This was just in my free time between studying for a shelf exam and writing some H&Ps.
My apologies if it is received as rambling, excessive, or confusing.
I only hope my area of study and work can help other people better understand these processes. If everyone already knows this, my apologies again
Edit 1: Changed "grains" to "wheat"