Brain may sabotage effort to diet

When lean people have full stomachs, neural signals cause their brains to stop wanting food. The positive feelings associated with food are turned off. But a new study from Yale reports that the brains of obese people react to food differently.

Willpower and reasoning
In this study, 9 lean and 5 obese adult volunteers underwent brain scans while looking at pictures of foods such as ice cream, french fries, cauliflower, or a salad. All the volunteers arrived for the first scans with empty stomachs and relatively low blood sugar, and all of them reported wanting the food in the pictures, especially the high-calorie food. For all 14 hungry volunteers, the scans showed that the brain areas that control positive reinforcement and desire for food were active and turned on, but the parts of the brain associated with willpower and reasoning, such as the prefrontal cortex, were not active. No surprise there. When we're hungry, food is attractive and eating feels good. And we're reluctant to stop until the hunger is gone.

Unexpected findings
The interesting part of the study occurred when the volunteers arrived full and sated, with normal blood-sugar levels. It turns out, the brain scans of the obese volunteers were the same whether they were full or hungry. The part of the brain that controls desire for food and regards food as positive reinforcement were still active even when their stomachs were full. And the part of the brain that regulates willpower and reasoning was still inactive even when they were full.

In contrast, the brain scans of the lean volunteers with full stomachs showed a decrease in their desire for food, and higher activity in the part of the brain associated with reasoning and willpower.

Implications are huge
Yale endocrinologist Robert Sherman, coauthor of the new study, says the surprise was that the part of the brain that regulates willpower over eating was mostly turned off in obese people, regardless of hunger and blood-sugar levels. The implications of this study are enormous. Coauthor Sherman says the findings suggest that brain functions "may perpetuate obesity."

So what now?
What's the solution? Most weight-loss programs say keep the high-calorie foods out of the house. If we have to nibble, we should go after the fruits and vegetables. That's not so easy this time of year, with all the attention to holiday foods. We can't control what shows up on the platters at holiday gatherings. But it may be a little easier to control what we keep in our kitchens.

8 Egregious Animal Abuses by the Meat Industry

This is the third post in a series about reasons to consider a vegan diet.

Earlier:
Top 5 Ways Livestock Wreck the Planet
Top 7 Health Reasons to Bypass Animal Products

While researching our books Veggie Revolution and Going Green, Sadie and I wrangled our way into several factory farms - our home state of N.C. is full of them. North Carolina has more hogs than people, and is a major poultry state too. Why? Because land is cheap, environmental laws are lax, and NC is the least unionized state. So the meat industry is free here to exploit immigrant and minority labor and pollute our rivers. Smithfield has the world's biggest hog "processing plant," in Tar Heel, NC, where 35,000 hogs per day are slaughtered. The Cape Fear River runs right by, to receive the effluent. Most states that produce a lot of animal products exclude farm animals from animal-cruelty laws. So anything that's common practice in animal farming is legal, regardless of how abusive or cruel it is. Hundreds of inhumane practices warrant comment in a post such as this. But I chose situations I witnessed while researching our books - those that had the biggest emotional impact on me.

A sow confined in a farrowing crate with her piglets. Photo: Sally Kneidel

1. Most breeding sows in the U.S. spend their lives in "gestation crates" so small they can't turn around.
The sows have no bedding, no straw, nothing to do but lie there - for 12 years. They breathe the foulest air you can imagine - after I walked through the buildings, everything I had reeked of fresh feces, including my camera. The rooms with rows of "farrowing crates" were the saddest sight, for me. Just before piglets are born, a sow is transferred from her gestation crate to a farrowing crate, where a metal bars (see photo) immobilize her and keep her teats always available to the piglets. The piglets are removed after 3 wks, then the sow is inseminated again and moved back to the gestation crate. Under pressure from animal activists, some pork producers have pledged to phase out gestation crates by 2017. But these narrow, bare crates are still the norm. Veterinarians consider pigs as smart as dogs, and without ample places to root and explore, pigs are bored to the point of insanity. Imagine keeping a dog for 12 years in a crate so small it couldn't turn around. The public wouldn't stand for it. So why do we allow it for pigs?

  5-week-old chickens in a Tyson broiler shed. Photo: Sally Kneidel

2. The Tyson broiler farm I visited had 24,000 chickens crammed into each shed.
As I entered a dimly-lit broiler shed, I felt claustrophobic - the air was so thick with feather and fecal dust that I had trouble breathing; the floor was spongy with 18 months' accumulation of feces. The chickens in the shed were crowded, but would get much more crowded after 2-3 more weeks' growth. Crowding maximizes profits by maximizing the number of birds in the expensive heated space, but also by keeping the birds immobile - inactive birds gain more weight. Tyson chickens are bred to be constantly hungry and to grow unnaturally fast, gaining 6 lbs in 7-8 weeks, most in the breast muscles (the most expensive cut). Some gain so fast their legs collapse and they starve, unable to reach the automated food and water dispensers. The farmer has to do a "walk-through" every day to pull out the dead birds. When the chickens have reached the target weight for slaughter at 7-8 weeks, a crew of Tyson "catchers" come in. Hidden cameras have shown the catchers literally throwing the live chickens into the crates (up to 5 birds per hand is allowed). For a description of the slaughter and processing of the chickens, read this excerpt from the book The Way We Eat by Peter Singer and Jim Mason.

3. Breeder chickens must be kept hungry all the time, or their own weight will kill them.
We visited a Tyson breeder farm, which produces fertile eggs and chicks to populate the broiler sheds. The breeder or parent chickens are allowed to live for 63 weeks (much longer than broilers) because they have to reach sexual maturity, unlike the broilers. The shed we visited contained 11,500 hens and 1,200 roosters. The breeders, being older, are bigger than broilers (9 lb hens, 12 lb roosters). They looked to me just as tightly packed in the shed as the broilers were, but the farmer said they're not, because the roosters have to be able to move around to reach all the hens. As the hens lay fertile eggs in their roosting boxes, the eggs roll out of the shed by automation, then are transferred elsewhere to hatch into chicks. Since the breeders (as parents) must have the same genes for hunger and weight gain as the broilers, the breeders could all grow to fatal proportions with their longer life spans. To prevent this, the breeders are fed minimal diets and are always hungry, said the farmer. These chickens have also been bred to lay eggs with abnormal frequency, and around 10% of the hens drop dead from "blowout" - the physiological stress of egg overproduction with a minimal diet.

Laying hens at Food Lion egg factory. Photo: Sally Kneidel

4. At the Food Lion egg factory I toured, five hens were stuffed into each 18" x 20" cage.
Cages were stacked floor to ceiling, housing 1.2 million hens at the site. These hens lay "table eggs" for human consumption. Each hen, with beak clipped to prevent fighting, spends 2 years in a cage until her body is spent. "When they're done," said the manager, "we can hardly give them away." Walking up and down the aisles, I saw the hens had bare red patches and stripped feathers from trying to dust bathe on a metal grate and trying to brood missing eggs - the eggs roll onto the conveyor belt as soon as they're laid. Many had feces on their heads and shoulders from the hens stacked above them. The hens have been engineered to lay 3 times the number of eggs as a normal rural hen. If the rate of production wanes, food is withheld for several days, which forces the hens to molt, and then egg production picks up. An occasional "forced molt" is recommended by the industry to maximize production. The sheds where hens were undergoing a forced molt were very quiet. This was the worst air of all the factory farms I visited - there was a dusting of "snow" (fecal and feather dust) on everything, including me. Under the cages was an 8' ft deep trench full of hen feces. It's emptied only when the hens are replaced, every 2 years. The buildings had outdoor fans, but none were operational.

5. "A dairy cow is a milk factory. There's not much quality of life in a dairy cow,"
said the dairyman. A family dairy cow used to produce milk for 10 to 12 years, maybe live as long as 20 years. Nowadays, in the industrial-sized dairies that can house 10,000 to 18,000 cows each, a cow is generally worn out after only 3 years - her body is pushed to its limits and just gives out. In one of these mega-dairies, a cow is impregnated roughly once a year to maximize her milk production. She may also be injected every other week with BST (bovine somatotropin) to increase milk production 10% more. The continual pregnancies and abnormal milk production place a huge strain on the cow's body. The concrete floor is hard on her feet and legs, and the weight of pregnancy makes it more so. When her milk production drops too low or she has chronic leg problems or fails to become pregnant, she's slaughtered for low-grade meat. In a typical confinement dairy, a third of the herd is culled every year. What happens to the calves that result from the continuous pregnancies? Many consumers have the impression that humans take the milk the calf doesn't want. But the calves are whisked away from mom only a few hours after birth. Female calves may be raised on formula to replace the milk cows culled from the herd. Male calves may be sold at auction, or tethered alone in wooden stalls for 16 weeks, fed low-iron diets to make their flesh pale, and then slaughtered to be sold as veal. How do cows feel about losing their calves just after birth, when their systems are flooded with mothering hormones? They look for the calf and often bellow continuously, sometimes for weeks. Said Dr. Temple Grandin, "That's one sad, unhappy, upset cow. She wants her baby....it's like grieving, mourning."

6. The unnatural corn diet fed to 90% of beef cattle makes them very sick.
Cows evolved to eat grass. But corn leads to faster weight gain, so at 6-7 months of age, 80-90% of beef cattle are transitioned to an abnormal diet of up to 85% corn. At the same time, they're trucked to large feedlots; one feedlot may have as many as 200,000 steers, grouped in pens of 900 or so. The cattle spend all their time standing or lying in a gray muck of feces and urine, with access to an always-full trough of corn and food additives, until they reach slaughter weight at 12-14 months of age. Corn causes cattle stomachs to be more acidic than they should be. The industry's "Feedlot Magazine" says all corn-fed cattle develop painful "sub-acute acidosis" at some point in the feedlot. The "Beef Cattle Handbook" (for feedlot managers) says animals with sub-acute acidosis "are plagued with diarrhea, go off their feed, pant, kick at their bellies, salivate excessively, and eat dirt." This condition often leads to very painful stomach ulcers, which when perforated, lead to liver ulcers. "Acute acidosis" is generally fatal. Feedlot management is a race between erosion of the digestive system and growth to slaughter weight. An effective feedlot manager sees to it that growth wins and the animal reaches slaughter weight before it succumbs to disease. For more details about feedlot life, see Michael Pollen's article "Power Steer." For info about what goes on in cattle slaughterhouses, read Fast Food Nation by Eric Schlosser.

7. Are fish insensitive, just because they're not mammals?
Fish are smarter than you might think. I studied the behavior of cichlid fish as a project in college, and I was astonished when I realized the school of fish that I was observing all recognized me personally.  Their tank was was in a hallway constantly full of other biology students, but when these fish saw me nearby, they all immediately came to the surface and toward me - because they knew I was the one who fed them. This was regardless of what I had in my hands. Several studies report fish intelligence, and sensitivity to pain. Dr. Culum Brown trained fish to find a hole in a net on only 5 attempts. When re-tested 11 months later, the fish remembered instantly. Dr. Lynne Sneddon showed experimentally (with bee venom and acetic acid) that rainbow trout feel pain and distress, make efforts to relieve the pain, and show relief when injected with morphine. Fish are the only vertebrate animals harvested on an industrial scale, with long-lines, gill nets, bottom trawlers, etc. Death by suffocation takes about 15 minutes; others are clubbed, pulled aboard with pickaxes, or bleed out when their gills are cut off. We treat fish as if they're vegetables, and we do it to a lot of them - humans haul in 88 million tons of fish each year just from the oceans. I haven't mentioned our decimation of fish populations - read about that here. For more about the sensitivity of fish, click here. For info about farmed fish, click here and here.

8. Foie gras - who would eat it?
Fois gras is the liver of a duck or goose that has been fattened by force-feeding it a mash of corn boiled in fat. The animal is fed far more than it would normally eat; a funnel with a long tube is used to push an excessive volume of food into the bird's esophagus 2-4 times per day. The resulting fatty liver of the bird is considered a delicacy by some, especially in France. But many investigators have reported that the birds live a miserable life: grossly overweight, immobile, with numerous damaged organs. For more info about foie gras, read here. To see a video of Kate Winslet's comments on the cruelty behind foie gras, click here.

Keywords: factory farming animal cruelty animal welfare hog farms poultry farms fish feedlots breeder farms humane farming foie gras

Top 7 Health Reasons to Bypass Animal Products

Nicci and Sadie chop onions for a vegan stew. Photo: Kneidel

Previous post: Top Five Ways Livestock Wreck the Planet

1. Protect your heart. Multiple studies report that the consumption of beef, pork, and lamb increase the risk of heart disease. Cardiologist Caldwell Esselstyn, in a 20-year-study, found that patients who adhered to his plant-derived diet reduced their cholesterol from an average of 240 mg/dL (high risk) to below 150 mg/dL - the total cholesterol level seen in cultures where heart disease is essentially nonexistent. In addition, Esselstyn's patients who had already experienced heart attacks or bypass surgery, etc., had virtually no further cardiac events after adopting his diet. His work is featured in the new documentary PLANEAT.

2. Vegetarians are 40% less likely to get cancer compared to meat-eaters, according to the Physicians Committee for Responsible Medicine. Colon cancer is one of several cancers linked to meat consumption. Total fat and saturated fat, which tend to be higher in animal products than in plant-derived foods, increase colon-cancer risks. The same is true for breast cancer. Countries with a higher fat intake, especially fat from meat and dairy products, have a higher incidence of breast cancer. In Japan, for example, the traditional diet is much lower in fat, especially animal fat, than the usual western diet, and breast cancer rates are low. In the 1940s, when breast cancer was very rare in Japan, less than 10% of the calories in the Japanese diet came from fat.

3. Milk is a "stew of hormones"
Recent studies in adults have linked cow's milk with an excess cancer risk in the prostate, and to a lesser extent in the breast and ovaries, notes oncologist Michael Pollak of McGill University. Researchers suspect milk's "natural stew of hormones, growth factors and other biologically active chemicals" to be causative agents, reports Janet Raloff in Science News. Scientists at the National Cancer Institute analyzed grocery-store milk and found that whole milk contains the smallest quantity of estrogens; skim and buttermilk contain the most. Here's a quandary: although whole milk may contain the least estrogens, it contains the most saturated fat. And saturated fat has been associated with colon cancer for some time. What to do? Jettison the milk. See my previous post about milk and cancer.

4. Diabetes and obesity associated with meat-eating
An August 2011 study in the American Journal of Clinical Nutrition suggests that eating as little as 1 daily serving of red meat (beef, pork, lamb) increases your risk of type 2 diabetes. In the study, one daily serving of unprocessed red meat raised the diabetes risk about 20%. Worse, "one serving per day of processed meat like a hot dog or sausage was associated with a 50 percent increased risk of diabetes” said study co-author Dr. Frank Hu of the Harvard School of Public Health. “That’s pretty high.” In addition, those who ate the most red meat were less likely to eat fruits and vegetables and more likely to be obese and to smoke. “I think we should change our mindset in terms of protein sources in our diet,” said Dr. Hu. For the summary article, click here. For my previous post about fast foods and health, click here.

5. Fish infused with mercury
U.S. coal-fired power plants release over 48 tons of mercury into the air annually; Asia releases even more. All this airborne mercury winds up in freshwater and oceans - and in fish. The EPA says a mercury blood level below 5.8 mcg/L is safe for pregnant women; the agency estimates that at least 8% of U.S. women of childbearing age have blood mercury levels higher than that. In the Northeast, 20% of such women do. In NYC, 25%. One San Francisco physician found that 89% of patients who said they often eat fish had elevated levels. Symptoms are neurological, ranging from loss of balance to cognitive problems. Says Dr. Nicholas Fisher of Stonybrook, "95 to 100% of the methylmercury in our bodies comes from eating seafood." When the EPA tested predatory and bottom-dwelling fish from 500 lakes, they found mercury in every single one; half were unsafe to eat. Another study by the USGS found mercury-contaminated fish in all 291 streams and rivers they tested. Are any fish safe to eat? If you want to check it out, go to gotmercury.org or epa.gov/ost/fish. For more info, see Sierra Magazine's Nov/Dec 2011 article "This much mercury...how the coal industry poisoned your tuna sandwich."

6. One egg has twice the cholesterol of a Quarter Pounder with Cheese
Aside from the periodic salmonella outbreaks, even uninfected eggs can be a hazard to your health. According to Susan Levin, writing for the Physicians Committee for Responsible Medicine, 70% of the calories in an egg are fat calories. Eggs also have "a surprising load of saturated fat, which causes the liver to produce more cholesterol, which in turn increases the risk for cardiovascular disease." A typical egg contains 212 milligrams of cholesterol, more than the 2010 Dietary Guidelines Advisory Committee recommends for an entire day. An egg contains more cholesterol than a McDonald’s Quarter Pounder with Cheese, which sports a hefty 94 milligrams of cholesterol. There is no recommended minimum intake of cholesterol, but 200-300 mg is the recommended daily max.

7. Chicken is "one of the most dangerous...."
Time magazine has called chicken one of the most dangerous items in the American home. Recent studies report that more than 30% of U.S. chicken is contaminated with Salmonella, and 62% is contaminated with Campylobacter. According to the USDA, these two pathogens cause 80% of the illnesses and 75% of the acute deaths associated with meat consumption. Regarding the saturated fat issue: many consumers have replaced red meat with chicken, believing chicken to have less fat. But chicken is not low-fat. According to The George Washington University Health Plan, "Three ounces of lean top round has 5 grams of fat, while three ounces of roasted chicken thigh has 13 grams of fat. Even without the skin, the roasted thigh has 9 grams of fat." For more info and sources about human health and poultry, click here.

What to do?
Avoiding animal products is no longer difficult, given the profusion of substitutes in today's grocery stores and farmers markets. For ideas on family meals, check out some of the menus and cookbooks reviewed on this site.

 Sadie peruses local produce at a farmers market. Photo: Sally Kneidel

Coming soon: Top 5 Humane Reasons to Choose a Plant-based Diet and Skip the Animal Flesh

Keywords: vegan health animal products vegetarian health health hazards of meat health hazards of eggs health hazards of milk health hazards of animal products healthiest diet healthy diet