There has been a lot of information that supports the notion that a person's mood has an influence on their food selection. A series of studies has shed some light on how mood may effect how we see our food. The first study found that people in a positive mood were more likely to rate nutritious food as favorable to more indulgent foods. The second study found that people in a bad mood were more likely to rate indulgent food more favorably nutritious food. The most interesting finding from this group of studies is that a person's mood affected something called time construal. A good mood allows people to make decisions that are more beneficial in the long term, such as choosing healthier food that will lead to better health down the road. People in a bad mood are more likely to make decisions that lead to immediate satisfaction, such as the relief many people experience from the taste of indulgent foods. The researchers recommend a double whammy approach to solving the problem of bad food choices in the face of a bad mood. By focusing on the future effects of food while at the same time providing mood relief in a form other than food, such as talking with a friend or exercising, may help you make better food choices when in a bad mood.
An amino acid found in spinach and eggs has been shown to improve reflexes/reaction time. The amino acid L-Tyrosine was shown to enhance reaction time when subjects were told to press a button as quickly as possible once a green arrow flashed on a computer screen. The subjects performed the task faster when they were told to drink orange juice fortified with L-Tyrosine versus when they drank unfortified orange juice. This effect jibes with L-Tyrosine's role as a precursor to neurotransmitters, particularly dopamine and norepinepherine.
People often associate the development of Type 2 diabetes with obesity and believe it to be due to recent weight gain. A recent analysis of data from the Whitehall II study indicate this may not to be true. The researchers looked at data compiled over the course of 18 years and found that obese people who developed Type 2 diabetes fell in to 3 groups. The largest group (94%) was comprised of people who were stably overweight throughout data collection, with a worsening of insulin function 5 years prior to diagnosis. The next group was comprised of people who gradually gained weight over the time of data collection (2.3% of diabetics), they noticed a sharp worsening of insulin function a few years prior to diagnosis. The final group was comprised of people who were severely obese throughout the 18 years(3.7%). These people noticed early increases in insulin secretion followed by decrements in the function of the cells responsible for insulin secretion.
Using accelerometry-based technology, things like the Nike Fuel Band and the Fitbit, researchers have been able to identify activity patterns in obese and healthy Americans. As a whole, Americans spend 15 hours per day either siting or sleeping. Obese people spend less than a minute per day engaged in intense physical activity and have lower amounts of general physical activity compared to everyone else. They also slept less which means they spend more time sitting than their counterparts. The negative effects of these habits on genetic expression pretty much put to rest the notion of the healthy obese.
If you're from a northern latitude you are more likely to be obese than someone in a southern latitude. The same holds true for animals, those in more northern latitudes tend to be larger than their counterparts in southern ones. It turns out that gut bacteria may have something to do with this. In a study looking at the geographical variation of gut bacteria between people, scientists found that people in northern latitudes had a microbiome that more closely resembled that of an obese person than people living in southern latitudes. Obese people tend to have more firmicutes and fewer bacteroidetes than lean people, and as the scientists looked at how the ratio of these two types of bacteria varied by geographic location. They found that the amount of firmicutes increased as you moved north while the amount of bacteroidetes decreased. They believe this is a result of people in the more northern latitudes having a microbiome that more effectively extracts energy from food. This makes sense, for most of our evolution the winter months are a time when food was typically not as plentiful as it would have been during the spring and summer. Being able to extract more energy would have been an advantageous thing, at least until food became plentiful and not so seasonal.
In other gut bug news, scientists have identified an enzyme in a prominent species of bacteria found in the human gut that helps them digest phytates and released some of the nutrients phytates bind to. In addition, this enzyme is also a means of communicating between this bacterium and our cells. The enzyme is found in something called an outer membrane vesicle(OMV) which allows phytates in where the bacteria can liberate nutrients. The enzyme also appears to be a method for altering calcium signaling in cells of the colon, which can affect any number of processes in these cells.
Regular daily physical activity such as walking may cut women's stroke risk by 20% and help ameliorate some of the increase of stroke risk in women undergoing hormone replacement therapy. If it seems like I'm beating a dead horse with all of these walking recommendations, it's because most people fail to realize that 4-5 hours of exercise per week is not the same thing as getting sufficient physical activity every day. Sufficient physical activity would be getting in more than 10,000 steps per day or walking approximately 5 miles per day. For most people, their general daily activities will get them at least 4,000 steps, after that it's basically just an extra hour of walking every day.
Finally, if you wondered why nutrition research changes so much and how it's so difficult to follow, Gary Taubes gives a pretty good rundown on why the nutrition research that many of us read about is so flawed. Check it out here.
