Matt Metzgar

Winter Metabolism: Leaves

2010-03-08T19:11:13-05:00

Earlier, a commenter pointed out how leaves in the spring could signal the body to release fat. The idea is that green leaves signal the arrival of spring and greater food availability, and therefore consumption of green leaves signals the body to release winter fat.

I found an interesting paper to support this. The tested how the addition of thylakoids derived from spinach leaves would affect hunger in healthy individuals. Adding the thylakoids decreased hunger and insulin. Also, a rat study showed that thylakoids suppressed hunger as well.

The Heat Is On

2010-03-07T14:02:51-05:00

I have written before about how Vitamin D supplements are not an adequate substitute for sunlight. Following up on this, I have found a few things related to "thermal therapy". Usually this is done with infrared saunas, which mimic and strengthen certain aspects of sunlight.

There have been a number of studies on this subject showing possible benefit. This study shows how thermal thrapy improves peripheral artery disease. This study shows how it helps those with chronic heart failure. In fact, the group using thermal therapy in this study had about a 50% less risk of death.

Overall, the evidence is not yet conclusive. Give it time and I think it will be. Until then, I will stick with sunlight and heat over supplements.

Crockpot Cooking

2010-03-07T13:06:55-05:00

I have been cooking with a crockpot for a few years now. I usually add in beef broth along with the water, but this morning I looked at the ingredients of beef broth. It seemed to have a number of strange ingredients, none of which I really want.

In the book, "The Fat Resistance Diet", the author recommends marinating meat in juice. He discusses how the cooking of meat can generate free radicals and lipid peroxides. He mentions how many cultural dishes that have been around for hundreds of years combine meat with anti-inflammatory foods and spices in the cooking process.

This morning I added in some orange juice and spices in place of the beef broth. In the whole scheme of things, this is probably a minor change, but hopefully it will provide some long-term benefits.

Waterworld

2010-03-05T19:29:09-05:00

A while back, a reader asked if water could play a role in the acid-alkaline balance in the body. After looking into it, I believe that water can play a role.

In Paleolithic times, the water that was consumed would be what is considered spring water or mineral water today. I think mineral water is particularly of interest.

A couple of studies have shown beneficial effects from mineral water. This study showed that subjects can absorb magnesium just as effectively from mineral water as they can from a magnesium supplement. This study shows that mineral water can contribute to daily calcium and magnesium needs.

Overall, I feel that mineral water is a healthy, natural option. It most likely moves the body towards an alkaline state as well.

Crazy Inflammation

2010-03-05T19:16:18-05:00

Here's an interesting study. It looks at the connection between chronic inflammation and behavior. It found that subjects with high levels of inflammation were more likely to be neurotic and less likely to be conscientious.

This is just another reason to avoid chronic inflammation!

Winter Metabolism: Fats

2010-03-04T19:17:11-05:00

Another piece to the puzzle is how do fatty acids fit into this theory. First, we know that as the omega-6 to omega-3 ratio has gotten worse in the U.S. over the years, people's health has declined. The next question is how does this relate to the different seasons.

Prompted by an earlier commenter, I found this fantastic article by Susan Allport. She discusses how omega-3s are "spring fats" and omega-6 are "fall fats". Spring fats cause us to lose weight in preparation for mating season, while fall fats tell us to stock body fat for the upcoming winter. There are additional followup articles at Susan's website.

This idea about spring fats and fall fats leads to other connections. First, you can look at nuts, which are an autumn/winter food. Over at the Paleo Diet website, this table show the omega-6 to omega-3 ratio for various nuts. Almost all the nuts listed have a very high n-6/n-3 ratio. Is this just a coincidence that these fall foods have a high ratio? I doubt it. Most likely, the changing fat ratio in these fall/winter foods signals the body to store fat.

I don't want to make it sound like nuts cause obesity. In studies, nut consumption may produce only produce a small weight gain. The normal cycle of the winter metabolism probably only produces slight weight gain. It is the idea of a modern person being in a continual winter mode that could ultimately lead to obesity.

The next question is how available are omega-3s during the summer months. Another graph from the Paleo Diet website shows the changing fat levels of wild game over the season:

The omega-3 fats (polyunsaturated) are not that prevalent in the summer months. However, if you believe that seafood played a large role in the Paleolithic diet, then you have your answer as to why omega-3s are a summer food. Fatty fish with their high omega-3 content are most prevalent in the summer months.

There is one other way to tell if omega-3 fats are a summer food. You could find out if the consumption of omega-3s gives skin protection from the summer sun. As it turns out, they do. This document shows how omega-3 fats provide skin protection from "the inside out" in terms of UV radiation.

Overall, this shows how fatty acids may play a role in shifting the metabolism into winter mode. The modern diet tends to be low in omega-3s and high in omega-6s. Refined foods and junk food often contain vegetable oils, which have high levels of omega-6 fats. Shifting towards "spring fats" like omega-3s may facilitate weight loss.

Winter Metabolism: Sunshine

2010-03-01T19:27:43-05:00

For the winter metabolism hypothesis to be correct, sunshine should affect a person's weight. I mentioned earlier that body fat is lowest in the summer. However, we don't know for sure if people are going outside and actually getting more sun in the summer.

A different way to test this would be phototherapy. Phototherapy should help an overweight person lose weight, because it signals the body that winter is over.

I found two studies on this. The first study was only a small study, but it did generally show this result. The study showed that three of four obese patients lost weight from phototherapy.

The second study added phototherapy to a moderate exercise program. The researchers found that the addition of phototherapy had a significant effect on body fat. In fact, body fat only decreased in the exercise and light group. It did not change in the exercise only group.

Winter Metabolism: Fruit

2010-03-01T19:16:46-05:00

A couple of people have mentioned the book, "Lights Out", which I read years ago. I thought it was a solid book that made many good points. In addition, I would point out the book, "Diet Evolution", which makes similar points.

On of the core ideas in both books is that fruit is a signal to the body to store fat. I disagree with this. First, it should be noted that fruit is anti-inflammatory. In particular, citrus fruit seems to have a lot of anti-inflammatory effects (and berries, too).

So does fruit really signal the body to store fat? No, in fact I think it's the reverse. This new study shows that a higher fruit intake led to more subsequent weight loss. And there are other similar studies like this one.

If anything, I would say it's the absence of fruit which could lead to weight gain. No available fruit would be a signal to the body that summer is over, and that it's time to store fat for the winter.

Winter Metabolism: Taubes

2010-03-01T19:00:00-05:00

A commenter noted how this theory might be similar to those of Gary Taubes. I agree, and as I thought about this theory, I thought about how this theory is Taubes-like.

Taubes wrote that weight gain was a function of hormones. In his view, carbohydrate intake changed the hormonal balance which led to weight gain. Overall, I think his theory is flawed, but the same type of principle applies here: weight gain is hormonally controlled, except that I'm saying it has to due with the body reacting to seasonal factors.

Let's compare the two theories. Taubes paints carbohydrates as the villian, even though there are cultures who eat high-carb and who are not overweight. Even in the U.S., if you go back to the year 1909, Americans were eating 500 grams of carbohydrate per day. If you look back at old photos from that period, I don't see too many overweight people.

With the winter metabolism, you possibly have a mechanism that has been around for millions of years. With a normal food supply and sunlight, the mechanism worked as intended. With a variety of factors in the modern diet (which I will further detail) and a continual lack of sunlight, the mechanism may be running virtually all year round.

Winter Metabolism: Obesity

2010-03-01T18:47:40-05:00

I wanted to clarify one thing about the winter metabolism that I wrote about. I am not saying that winter (or lack of Vitamin D) causes obesity. Instead, I am saying that the modern diet and lack of sunlight can put a person in continual winter mode, such that obesity is the result over the long run.

In normal situations, perhaps the winter season leads a person to gain a few pounds and then they lose that weight in the spring/summer. Nowadays, the modern diet and indoor living trap a person in this winter cycle. The result is slow weight gain over the years and other associated health problems.