Sunday, May 22, 2011

Technology and Diet

I believe that the majority common diseases and disorders plaguing humans these days are a direct consequence of technology changing our environment too rapidly for us to adjust. Humans were simply just not made for a world with instant access to all kinds of food, electric lighting, lifestyles requiring hours of sitting indoors, automated transportation, arch support, and the removal of labor from its fruits.

In a recent issue of JAMA (2011;305(13):1352-1353) David Ludwig (Md., PhD, Children's Hospital) weighs in on this topic, commenting on how rapid changes in food technology have affected our overall health. He outlines several ways technology might be reappropriated for increasing general nutrition. He closes, "Reducing the burden of obesity-related chronic disease requires a more appropriate use of technology that is guided by public health rather than short-term economic considerations." You think? Good luck.

Excerpt: Technology, Diet, and the Burden of Chronic Disease

"[Historically]...food has been either difficult to get or difficult to eat. Humans lack the strength and speed of large carnivores and the specialized digestive track of herbivores…For this reason, humans have long strived to develop technologies to improve food availability, digestibility, safety, transportability, and storage life. However, the rate of change in food technology has greatly accelerated, with major implications to human nutrition and health.

THREE REVOLUTIONS IN FOOD TECHNOLOGY

…About 12 000 years BCE, domestication of staple grains ushered in the Agricultural Revolution, fostering a huge increase in available calories, a massive expansion of human populations, and creation of civilization. However, the advent of agriculture also caused the first widespread occurrences of protein- and micronutrient-deficiency diseases, because grains tend to have a lower ratio of nutrients to calories than animal and other plant foods. Archeological evidence suggests that mean stature decreased by several inches with transition from a hunter-gatherer to agrarian lifestyle,1 a loss that has only recently been recovered in Western countries.
The Industrial Revolution of the 19th century allowed for mass production of refined flour and concentrated sugar, setting the stage for what might be termed the commodity-based diet, characterized by food extrusion technology, petrochemicals, and biotechnology. This era culminated in the widespread dissemination of ultraprocessed products such as fast food throughout the United States.

ULTRAPROCESSING AND CHRONIC DISEASE

Ultraprocessed products (a term coined by Monteiro et al2) may resemble natural foods, but actually represent a radically new creation…

The tremendous variety of ultraprocessed products marketed today derives predominantly from extreme chemical and mechanical manipulation of just 3 species—corn, wheat, and soy—and animals fed these commodities, representing a transformation from species diversity to product diversity of the diet. In an anecdotal report,3 a television reporter commissioned an isotopic analysis of his hair and found that 69% of the carbon could be traced to corn, highlighting Pollan's concerns about the dominance of this one species in the US diet.4
A diet based on ultraprocessed products may promote obesity and chronic disease through a variety of mechanisms, including high energy density; large portion size; low content of fiber, micronutrients, and phytochemicals; poor-quality dietary fat; high glycemic load; and high-intensity flavoring.
The removal of water during processing promotes shelf life and decreases transportation costs, but also increases the number of calories contained in a bite of food. Acutely, individuals regulate solid food intake by volume more so than calories.5 Over the long term, habitual energy density is inversely related to dietary quality and directly related to body weight. High energy density may promote overconsumption especially in the context of large portion sizes. When young children were given small, medium, or large portions of macaroni and cheese for lunch, calorie intake did not differ. However, intake increased with increasing portion size among older children, suggesting that individuals may lose the ability to recognize, or learn to disregard, internal satiety mechanisms in the modern food environment.6
Ultraprocessed products are concentrated in calories, but deficient in fiber, micronutrients, and phytochemicals (plant substances that may mediate some of the protective effects of vegetables and fruits against diabetes, heart disease, and cancer). A 10-oz, 90-kcal portion of strawberries has 5 g of fiber, significant amounts of several vitamins and minerals, and dozens of phytochemicals, whereas a 1-oz portion of Fruit Gushers also has 90 kcal but virtually none of these beneficial constituents.
Dietary fat quality of ultraprocessed food tends to be exceptionally poor, with reliance on trans fat and saturated fat (solid at room temperature) for product stability. These fats increase risk for heart disease,7 whereas protective polyunsaturated fats tend to be removed or destroyed in the manufacturing process. Similarly, food processing increases glycemic index, a measure of how quickly carbohydrate-containing foods increase blood glucose. In a multicenter study of 773 adults who had lost at least 8% of baseline body weight, individuals assigned to a low glycemic index diet regained significantly less weight over 6 months than those assigned to a high glycemic index diet.8 In addition, ultraprocessed products typically emphasize sugar, salt, and fat. This high-intensity flavoring, often further enhanced with artificial ingredients, may override endogenous satiety mechanisms and produce behavior akin to addiction…

TOWARD A MORE APPROPRIATE USE OF TECHNOLOGY

Food processing is a fundamental aspect of human culture and industrial methods are necessary to support a world population that now exceeds 6 billion. Extensively processed foods like refined flour, sugar, and oils have been consumed by humans for millennia as ingredients in meals made primarily from whole or minimally processed foods. The problem, as Monteiro et al2 argue, is the creation of a dietary pattern based on factory-made, durable, hyperpalatable, aggressively marketed, ready-to-eat or heat foodstuffs composed of inexpensive, highly processed ingredients and additives. Reducing the burden of obesity-related chronic disease requires a more appropriate use of technology that is guided by public health rather than short-term economic considerations.

Measures to Promote a More Appropriate Use of Food Technology
·         Government
o   Restructure agricultural subsidies to promote high-quality foods (eg, vegetables, fruits, and legumes)
o   Regulate food advertising/marketing, especially to children
o   Adequately fund school lunch and related nutrition programs
·         Public
o   Buy fewer ultraprocessed products
o   Prepare meals from basic ingredients in the home
o   Give preference to restaurants that prepare meals from scratch
·         Schools
o   Prepare lunch and snack foods from whole ingredients
o   Institute a new “home economics” curriculum to promote cooking
·         Restaurants
o   Provide intermediate option between gourmet food and fast food—convenient, inexpensive meals prepared from whole foods (eg, Chipotle Mexican Grill)
·         Industry
o   Use higher nutritional value ingredients vs commodities
o   Market minimally processed/traditionally processed products (eg, stone ground bread, steel-cut oats)
o   Use preservation methods that protect polyunsaturated fats"

Saturday, May 21, 2011

Coronary Bypass Grafts Compared to Non-Invasive Medical Therapy

An article in JAMA looked at the response of cardiologists to a recent study showing that medical therapy produced the same degree of protection against death as coronary artery bypass grafts (CABGs). The physicians were remarkably resistant to implementing the results of the study.
Excerpt:
"A trial of 2 treatment strategies for heart failure, one much more expensive and invasive, found that both provide the same degree of protection against death within about 5 years after initiating treatment. Such a finding suggests that cardiologists will opt for the cheaper and less invasive therapy, but that may not be the case.
At issue is treatment of patients with coronary artery disease and left ventricular dysfunction. At the American College of Cardiology scientific session here in April, researchers compared the efficacy and safety of coronary artery bypass graft (CABG) surgery plus optimal medical therapy with medical therapy alone. The Surgical Treatment for Ischemic Heart Failure (STICH) trial included 1212 patients with left ventricular ejection fraction of 35% or less and coronary artery disease amenable to CABG, who were randomized to either treatment strategy. After a median follow-up of 56 months, 218 of 610 patients randomized to CABG plus medical therapy died compared with 244 of 602 patients randomized to medical therapy alone; CABG plus medical therapy reduced death rates by 14% compared with medical therapy alone, but the difference did not reach statistical significance (Velazquez EJ et al. N Engl J Med. 2011;364[17]:1607-1616).
Those arguing that CABG should remain a viable treatment option for these patients point to secondary analyses showing that those who had the surgery had lower rates of hospitalization for cardiovascular causes or death. Robert O. Bonow, MD, a STICH coinvestigator and a professor of medicine at Northwestern University's Feinberg School of Medicine in Chicago, pointed out that this is the first prospective randomized study of these types of patients and treatment options and that it will take time to analyze the findings to identify patients who will truly benefit more from one treatment option than the other.
'There was a reduction in mortality with CABG, but it was not significant,” Bonow said. “But the secondary end points are intriguing. There is also a difference between a clinical trial and the way you interpret the result and the relevance it has in the clinical setting.'
But in an age of emerging clinical effectiveness research in which studies pit different treatment strategies against each other to find the best options, the fact that cardiologists are still arguing for CABG and offering it to patients in a shared decision-making environment baffles Harlan M. Krumholz, MD, professor of medicine at Yale University School of Medicine in New Haven, Conn. “When you are talking about open-heart surgery and the discomfort and risk and cost, shouldn't it have to be a superior strategy in order for us to have any enthusiasm to recommend it to our patients?” Krumholz asked. “And the idea that the patient has an equal choice seems to be putting the brightest possible light on truly a negative study.”

Monday, April 4, 2011

50 Miles

One of the Three Loops
A couple of months ago I decided to sign up for the Pineland Farms 50 Mile race in Maine on May 29. At the time, I thought it would be good motivation to get myself into shape. I always wanted to try a 100 mile race, and I thought that this would be a decent reality check that would probably get the crazy 100 mile idea out of my head. More than anything else, though, when I signed up May 29 seemed so far away that I thought I had more than enough time to get prepared. May 29 now seems way to soon, and I'm beginning to regret the whole idea. All of a sudden, it seems pretty dumb to try to run 50 miles when the farthest I've ever raced is a half-marathon. Looking forward to seeing how this one's going to turn out.

Here's the course description (My favorite line-"Although there are no major climbs the rolling terrain is unrelenting." Great.):

Participants in the 50 mile race will completea 3.5 mile loop, then 3 laps of the 25km course. The race course is a 25 kilometer off-road roller coaster on well-maintained XC trails that twist, turn, and roll their way through forests and across pastoral, working farmland. The trails are level, wide (12'), and non-technical with no roots or rocks, but very hilly. Although there are no major climbs the rolling terrain is unrelenting. The surface of the trails is mainly grass and dirt sprinkled with pine needles, pine cones, twigs, and small stones. From time to time runners will be directed off the main trail system and into fields. In the fields the course will follow a path cut by local farmers using their haying equipment. The grass is rough and can vary in height in different places. Some of the cut grass may still be on the path making running more difficult. There are no stream crossings on the course per-se, however, the grass in the fields can be very wet in the morning, and there may be wet and muddy spots if it rains just before the race. The paths in the fields are often not level, tilting severely in all directions. Trail running shoes are not necessary, but they are recommended.



Thursday, March 24, 2011

Prospect Hill Park

Boston in the distance
One of the worst things about living in our apartment in Waltham is how difficult it is to get away from the traffic and noise of the roads and find a nice place to run. Many times I have repeatedly run up and down the same sidewalk just because it was so nice to actually have a sidewalk to run on. Today, though, I discovered a pretty sweet little 100 acre park called Prospect Hill only a couple of miles from our apartment. As you would expect it is hilly, but it is crisscrossed by 4-5 miles of paved and unpaved trails and rewarded some of the steeper climbs with nice views of Boston. I know it's surrounded by urbanity, but it was quiet enough to hear the snow flakes as they hit the leaves on much of the run.
Garmin's Version

Thursday, March 17, 2011

Cruising Mahahual



Erica and I had a great time spending her spring break down in Mahahual, Mexico last week.



I only managed to run 3.5 miles last week while we were there, but it was a pretty sweet 3.5 miles.



Monday, March 7, 2011

Sea-Ice Algae

ScienceDaily (2011-03-07) -- Sea-ice algae -- the important first rung of the food web each spring in places like the Arctic Ocean -- can engineer ice to its advantage. The same gel-like mucus secreted by sea-ice algae as a kind of antifreeze against temperatures well below minus 10 C is also aallowing algae to sculpt microscopic channels and pores in ice that are hospitable to itself and other microorganisms.