LOOPTECHS

Healing Back Pain

On December 22, 2015 By jammy // No comments:

I've put off writing this post for many years because I know it will be controversial. But we're a few days from Christmas, and I also know this post will be a wonderful gift for some people.

Chronic or intermittent pain, often located in the back, neck, and/or buttocks, is a major driver of personal suffering and reduced productivity in the US and other affluent nations. While pain can obviously have a variety of structural causes, such as sprained ankles or bruising, garden-variety back pain usually doesn't. I've come to believe that such pain is usually psychosomatic in nature-- in other words, caused by the brain but resulting in physical signs and symptoms in the body. It's widely accepted that a person's mental state can affect pain perception, but this idea goes further. Pain isn't just exacerbated by a person's mental state; it's often entirely caused by it.

Read more »

New Evidence Strengthens the Link Between Hypothalamic Injury, Obesity, and Insulin Resistance

On December 10, 2015 By jammy // No comments:

Obesity involves changes in the function of brain regions that regulate body fatness and blood glucose, particularly a region called the hypothalamus. My colleagues and I previously showed that obesity is associated with inflammation and injury of the hypothalamus in rodent models, and we also presented preliminary evidence that the same might be true in humans. In our latest paper, we confirm this association, and show that hypothalamic injury is also associated with a marker of insulin resistance, independently of BMI.

Introduction

Read more »

Fat, Added Fat, and Obesity in America

On November 22, 2015 By jammy // No comments:

In the last post, we saw that carbohydrate and particularly sugar intake have been declining in the US since 1999, even as our obesity rate has continued to climb.

In this post, let's look at another putative driver of obesity: our fat intake, and especially our intake of added fats like seed oils, butter, and olive oil. Like the graphs in the last post, the data underlying the following graphs come from USDA food disappearance records (not self-reported), and NHANES survey data (1, 2). Also like the last post, the graph of total fat intake is not adjusted for waste (non-eaten food), while the graph of added fat intake is*. As a consequence, the figures for total carbohydrate and total fat intake are higher than actual intakes, but still good for illustrating trends.

Here we go. First, total fat:
Read more »

Carbohydrate, Sugar, and Obesity in America

On November 16, 2015 By jammy // No comments:

We like explanations that are simple, easy to understand, and explain everything. One example of this is the idea that eating carbohydrate, or sugar, is the primary cause of obesity. This lets us point our finger at something concrete and change our behavior accordingly. And it's true enough that it has practical value. But the world around us often turns out to be more complex than we'd like it to be.

The CDC recently released its latest data on the prevalence of obesity in the US, spanning the years 2013-2014 (1). These data come from its periodic National Health and Nutrition Examination Surveys (NHANES). Contrary to what many of us had hoped for after a slight decline in obesity in the last survey, the prevalence has once again increased. Today, roughly 38 percent of US adults have obesity. As a nation, we're continuing to gain fat, which is extremely concerning.

I decided to examine the relationship between obesity prevalence and our intake of carbohydrate and sugar over the years. The food intake data come from the USDA's Economic Research Service (2). For some reason, the data on carbohydrate don't extend beyond 2010. This probably relates to funding cuts at the USDA*.

Let's have a look at the data for carbohydrate:

Read more »

Food Reward Friday

On October 30, 2015 By jammy // No comments:

This week's lucky "winner"... the Reese's PBC Burger!!

Image credit: The Works

Do Processed and Red Meat Cause Cancer?

On October 26, 2015 By jammy // No comments:

Today, the World Health Organization's International Agency for Research on Cancer published a statement in The Lancet detailing its position on the carcinogenicity of processed and red meat (1). The statement, resulting from a meeting of 22 scientists from 10 countries, concluded that processed meat is a group 1 carcinogen, meaning that it is "definitely carcinogenic to humans". They also judged that red meat is a group 2A carcinogen, meaning that it probably causes cancer but the evidence isn't as strong. They're mostly referring to the links between processed and red meat and digestive tract cancer, particularly cancers of the colon and rectum.

These statements were met with a media frenzy, and the expected furor from the meat industry. The most surprising thing, for me, is that anyone would be surprised by the IARC's statement.

Read more »

Why Do Girls and Boys Reach Puberty Younger Than They Used To?

On October 16, 2015 By jammy // No comments:

Girls, and probably boys, are reaching puberty years younger than they did in our great-grandparents' generation. Why? There's no shortage of explanations, but the primary reason is probably quite simple.

Read more »

Will You Fill Out This Paleo Diet Survey?

On October 08, 2015 By jammy // No comments:

This week, I received an e-mail from a graduate student at Humboldt State University named May Patiño. She asked me to share her online research survey targeted to Paleo dieters. Here are the goals of her research, in her words:

The main objective of my study is exploring how the Paleo diet is being implemented in practice. I would like to assess the health outcomes of these practices, as well evaluate how closely they conform to, or deviate from ways this diet is being described in theoretical literature, and implemented in controlled diet trials. I also want to be able to use the data collected to help explain what is driving the popularity of the ancestral health movement. Ultimately, I would like this information to be used to better inform protocols for controlled diet trails.

The survey took me about 40 minutes to complete. You're welcome to participate whether or not you're on the Paleo diet. Please consider taking the survey, for the love of science!

Research Survey: The Paleo Diet in the US

That Time I Ate Most of a Large Pizza in One Sitting

On October 05, 2015 By jammy // No comments:

Two weeks ago, I had a brush with Extreme Eating. My experience illustrates some important principles of how the brain regulates appetite and body fatness-- and how it reacts to calorie-dense, highly rewarding foods.

Read more »

Out for Two Weeks

On September 15, 2015 By jammy // No comments:

I'll be out of town with limited internet until September 27th. Feel free to leave comments, but I won't be able to moderate them until I return. Sorry for the inconvenience!

How Much Does Sugar Contribute to Obesity?

On August 26, 2015 By jammy // No comments:

Last week, the British Medical Journal published a review article titled "Dietary Sugars and Body Weight", concluding that "free sugars" and sugar-sweetened beverages contribute to weight gain. But what are "free sugars", and why does the scientific literature suggest that the relationship between sugar intake and body weight isn't as straightforward as it may initially appear?

More Thoughts on the Recent Low-fat vs. Low-carb Metabolic Ward Study

On August 18, 2015 By jammy // No comments:

The recent low-carb vs. low-fat study has provoked criticism from parts of the diet-health community. Let's examine these objections and see how they hold up to scientific scrutiny.
Read more »

A New Human Trial Undermines the Carbohydrate-insulin Hypothesis of Obesity, Again

On August 13, 2015 By jammy // No comments:

The carbohydrate-insulin hypothesis of obesity states that carbohydrates (particularly refined carbohydrates and sugar) are the primary cause of obesity due to their ability to increase circulating insulin, and that the solution to obesity is to restrict carbohydrate intake. Numerous studies have tested this hypothesis, more or less directly, in animals and humans. Despite the fact that many of these studies undermine the hypothesis, it remains extremely popular, both in the popular media and to a lesser extent among researchers. A new human trial by Kevin Hall's research team at the US National Institutes of Health offers very strong evidence that the carbohydrate-insulin hypothesis of obesity is incorrect. At the same time, it offers surprising and provocative results that challenge prevailing ideas about diet and weight loss.