A few days ago, the USDA finally unveiled their (fashionably late) 2010 dietary guidelines—the first update they’ve made since 2005. Are you as excited as I am? Can we live without bread yet? Leave the fat on our dairy? Ditch the rancid vegetable oils? Gobble down butter and coconut oil without fearing imminent death? By golly, has the USDA finally pulled its head out of the soybean fields and given us something useful, emerging as a reliable authority instead of a food industry puppet?

Nah.

Contrary to my title, though, the new guidelines aren’t total hogwash. Just mostly. A few of their recommendations are passable, like these:

• Prevent and/or reduce overweight and obesity through improved eating and physical activity behaviors. (Duh.)
• Increase physical activity and reduce time spent in sedentary behaviors. (Duh.)
• Keep trans fatty acid consumption as low as possible by limiting foods that contain synthetic sources of trans fats, such as partially hydrogenated oils. (Duh.)
• Limit the consumption of foods that contain refined grains, especially refined grain foods that contain solid fats, added sugars, and sodium. (Yes!)

Unfortunately, the rest of the guidelines are the regurgitated—and often unsubstantiated—snippets we’re already inundated with. Case in point:

• Consume less than 10 percent of calories from saturated fatty acids by replacing them with monounsaturated and polyunsaturated fatty acids.
• Consume less than 300 mg per day of dietary cholesterol.
• Consume at least half of all grains as whole grains. Increase whole-grain intake by replacing refined grains with whole grains.
• Increase intake of fat-free or low-fat milk and milk products, such as milk, yogurt, cheese, or fortified soy beverages.
• Use oils to replace solid fats where possible.

According to the guideline packet, these recommendations provide “information and advice for choosing a healthy eating pattern” and are “based on the most recent scientific evidence review.” If you’ve read anything else on this blog, you probably know by now that I’m weary of trusting second-hand interpretations—the original data often tells a different story than the mouths claiming to interpret it. So instead of taking the USDA’s word as gospel, why not see what they’re basing their recommendations on?

Luckily, the USDA has a Nutrition Evidence Library, where they’ve compiled the studies they used to create their latest guidelines. Let’s dig in. (more…)