Clearly, I'm a bit ecstatic about this week's public health news. For one, Proctor and Gamble, the makers of Tide detergents, has agreed to decrease the amount of cancer-causing 1.4-dioxin in many of its products to decrease the human potential for developing cancer. Then, PepsiCo announced that it is dropping a brominated chemical (brominated vegetable oil, a known flame retardant) from its orange Gatorade (but not other products like Mountain Dew)! And finally, a report from the Federal Trade Commission shows that advertising to children by food companies has dropped by 19.5% in 2009 from 2006.
Although I am beyond ecstatic for all the positive changes going on in the food, beverage and chemical industries, this is only a drop in the bucket towards creating a healthier, less toxic America. How are you contributing to this process? Get involved through the Environmental Working Group - www.ewg.org, Women's Voices for the Earth - www.womensvoices.org/ - or do what Sarah Kavanagh, a 15-year-old high school student from Hattiesburg, Mississippi did after reading about the toxic effects of BVO in her Gatorade - Create a petition!
Together we can implement change!
SPENDING DECLINES ON FOOD MARKETING TO CHILDREN
Total spending by food companies on marketing to children was down 19.5 percent in 2009 from 2006, according to the results of a Federal Trade Commission (FTC) comprehensive study of food and beverage industry marketing expenditures and activities directed to children and teens. The study found that most of that decrease comes from less spending on television ads to youth.
At the same time, food companies stepped up their spending by 50 percent to market to children and teens using online, mobile, and viral marketing strategies. Overall, food companies allocated $1.79 billion on marketing to youth ages 2-17 in 2009.
A Review of Food Marketing to Children and Adolescents: Follow-Up Report gauges the progress industry has made since first launching self-regulatory efforts to promote healthier food choices to kids. It serves as a follow-up to the Commission’s 2008 report on food marketing requested by Congress. Additional information and key findings about the nutritional quality of foods within the product categories most heavily marketed to children or teens is contained in the report.
In a JAMA study using functional MRI (fMRI) brain scans to assess differences in brain activity when ingesting glucose versus fructose, Yale researchers (Dr. Sherwin, et al) found that fructose (table sugar and high fructose corn syrup) inferiorly suppressed hunger and satiety (fullness) when compared to glucose (found naturally in plants and combined with other types of sugars (naturally) to form carbohydrates and dairy products). Fructose activated parts of the brain that are not necessarily important in feeding and satiety behaviors, while glucose activated "regions that act in concert to 'read' the metabolic state of an individual and drive motivation and reward". The researchers also found that glucose, but not fructose, had effects on circulating "hunger" hormone levels (insulin and GLP-1). This important research continues to help piece together the biological and psychological mechanisms behind sugar addictions that lead to overweight, obesity and morbidly obese states.
Read the full article below:
"Glucose appears to temper brain activity in regions that regulate appetite and reward -- but fructose does not, researchers found.
In a brain imaging study, participants who had a drink sweetened with glucose had significant reductions in cerebral blood flow in the hypothalamus, while those who drank a fructose-sweetened drink saw a slight increase in activity (P=0.01), Robert Sherwin, MD, of Yale University, and colleagues reported in the Jan. 2 issue of the Journal of the American Medical Association.
Glucose also reduced activation in the insula and striatum, other brain regions that regulate appetite, motivation, and reward processing, while fructose did not, the researchers wrote.
In an accompanying editorial, Jonathan Purnell, MD, and Damien Fair, PhD, of Oregon Health & Science University in Portland, said the findings "support the conceptual framework that when the human brain is exposed to fructose, neurobiological pathways involved in appetite regulation are modulated, thereby promoting increased food intake."
As the obesity epidemic has grown, so too has consumption of fructose in the American diet, the researchers explained in their article. Fructose is found in both sucrose, or table sugar, and in high-fructose corn syrup, another common sweetener. It is valued because it's sweeter than glucose.
But studies show fructose may have different metabolic effects than glucose. For instance, fructose only weakly stimulates secretion of insulin, a hormone that can increase satiety, and attenuates levels of the satiety hormone glucagon-like peptide-1 (GLP-1) -- so researchers are concerned that it could possibly increase food-seeking behavior and intake.
To assess those effects, Sherwin and colleagues conducted functional MRIs (fMRIs) in 20 normal-weight, healthy adults who were given 75 grams of either glucose or fructose in a cherry-flavored drink, and then crossed over to a drink with the other sweetener.
Participants rated their feelings of hunger, satiety, and fullness before and after the scan, and the researchers took blood to assess circulating hormone levels.
Overall, the researchers found that glucose significantly reduced cerebral blood flow in the hypothalamus, while fructose did not.
Specifically, blood flow fell 5.45 mL/g per minute from baseline with glucose, compared with an increase of 2.84 mL/g per minute with fructose, for a mean difference of 8.3 ml/g per minute, they reported (P=0.01).
They also found that glucose reduced cerebral blood flow in the thalamus, insula, anterior cingulate, and striatum -- "regions that act in concert to 'read' the metabolic state of an individual and drive motivation and reward" -- compared with baseline (P<0.05).
In contrast, fructose reduced blood flow in the hippocampus, posterior cingulate cortex, fusiform, and visual cortex -- but also in the thalamus (P<0.05).
In terms of connectivity between brain regions, glucose upped the links between the hypothalamus and the thalamus and striatum, while fructose only increased connectivity between the hypothalamus and thalamus, but not the striatum -- the latter of which also de-activates once a person is sated, the researchers said.
"These findings suggest that ingestion of glucose, but not fructose, initiates a coordinated response between the homeostatic-striatal network that regulates feeding behavior," they wrote.
They also found that glucose, but not fructose, had effects on circulating "hunger" hormone levels. Glucose elevated levels of insulin and GLP-1 compared with fructose (P<0.001 and P=0.01, respectively).
Leptin and ghrelin levels, however, weren't significantly different between the two sugars, the researchers found.
The differences in brain effects between glucose and fructose also appeared to coordinate with ratings of hunger, since there was a significant difference from baseline in terms of fullness and satiety when participants drank glucose, but not fructose (P=0.005 and P=0.03, respectively).
Sherwin and colleagues cautioned that the study was limited because fMRI doesn't provide a direct measure of neuronal activity, and thus any clinical implications can't yet be determined.
Editorialists Purnell and Fair noted that while some researchers and clinicians warn that the total amount of calories is more important than the type of food when it comes to losing weight, the "reality ... is that hunger and fullness are major determinants of how much humans eat, just as thirst determines how much humans drink. These sensations cannot simply be willed away or ignored."
"The remedy remains eating less," they wrote, "but the means involve reducing the food element, if possible."
The study was supported by grants from the National Institutes of Health and the Yale Center for Clinical Investigation.
Neither the researchers nor the editorialists reported any conflicts of interest.
Primary source: Journal of the American Medical Association
Source reference: Page KA, et al "Effects of fructose versus glucose on regional cerebral blood flow in brain regions involved with appetite and reward pathways" JAMA 2013; 309(1): 63-70."
Dr. Maltz earned a Medical Degree and Master in Public Health from the University of Texas Medical Branch (UTMB) in Galveston, TX. She completed a combined Internal and Preventive Medicine Residency at UTMB in June, 2011. She then completed a 2-year Integrative Medicine Fellowship at Stamford Hospital in Stamford, CT, during which she simultaneously underwent an intensive 1000-hour curriculum created by The University of Arizona Integrative Medicine Program founded by Dr. Andrew Weil.