Wednesday, July 13, 2016

How often should I be changing my sneakers?

Although this is something that most of us don’t think about, this is actually a really important question. If you are doing cardio on a daily basis, or close to it, you really need to pay close attention to your footwear.

Most people think to change their sneakers when they look old and beat up and the tread is starting to wear down. By the time these signs of wear and tear are apparent, you are well passed the time you should have retired them.

The issue is the midsole, which lies between the rubber bottom of your sneaker and where your foot sits. The midsole provides the majority of the cushioning for your shoe, and is therefore vital to the protection of your joints from the impact of your exercise. 

The midsole wears out way before the other parts of the shoe do. So I tell all of my clients that no matter how new the rest of the sneaker looks, replace them after 6 months. 

You don’t have to throw them out. You can certainly wear them around the house or to go shopping or whatever, just not for your cardio.

If you have knee, hip or back issues, changing your sneakers consistently can be a simple way to reduce your pain and discomfort.

Effects of a low glycemic index, low glycemic load diet

The Study
Twenty six overweight women were randomized to a low glycemic index, low glycemic load diet or their usual diet for 12 weeks. All of the subjects were infertile at the time of this investigation and were on a waiting list for IVF treatment. By the end of follow-up, the women in the low glycemic group lost 10 lbs, reduced their BMI by 2 units and reduced their body fat by almost 4%. The women in the usual diet group had slight increases in all of these variables. The low glycemic group had 85.4% more oocytes retrieved than the control group and had 3 spontaneous pregnancies resulting in 3 live births. American Journal of Clinical Nutrition 2015; 102:1365-72.

Take Home Message
This is an interesting study for a couple of reasons:

1) It shows the efficacy of the low glycemic diet for weight loss. To lose 4% of your body fat and 2 BMI units in 12 weeks is extraordinary weight loss. I am not at all surprised, as I have been using this approach with my own clients for decades and have had great success with it.

2) The changes in oocyte retrieval and the 3 spontaneous pregnancies in the low glycemic group just goes to show you how the stabilization of blood sugar can benefit hormone levels and body systems in surprising and unforeseen ways. 

 

Legumes and weight loss

The Study
A meta-analysis was recently published that compared the weight loss impact of diets containing legumes to diets without them. Data from 21 trials were included. For those of you not familiar with them, examples of legumes are black beans, pink beans, pinto beans, lentils and hummus. Diets containing legumes reduced weight by .75 lbs.  The average duration of the trials was 6 weeks. American Journal of Clinical Nutrition 2016; 103:1213-23.

Take Home Message
Legumes are an extremely healthy dietary choice and it looks like they may be particularly good for your waistline. An extra three-quarters of a pound lost in 6 weeks may not sound like much, but if you kept it up for a year, this little habit can have a very nice impact on your weight.

Legumes are high in protein and fiber, which tend to promote satiety. They are also low glycemic and tend to promote a stable blood sugar. This may also act to decrease hunger and food intake.  The subjects in the studies included in this analysis averaged one serving of legumes per day.  Black beans, pink beans, pinto beans, lentil soup, and hummus are just a few ways to get legumes into your diet, which is a great idea if you are looking to improve your health and your weight.

 

Book Review: Always Hungry

Next up for review is Always Hungry. The author, Dr. David Ludwig, is an endocrinologist, researcher and professor at Harvard Medical School and the Harvard School of Public Health. I met him a few times when I was getting my Doctorate and I am a very big fan of his research. 

Introduction
This interesting book presents a weight loss strategy based on blood sugar stabilization. Dr. Ludwig uses his vast research experience to argue that refined carbohydrate foods, and the subsequent swings in blood sugar following their consumption, have much to do with the increases in obesity in the last 30 years. The book is broken down into 2 sections. The first section covers the research in the area of glycemic load/glycemic index in a truly impressive fashion. The second part presents the weight loss program, which includes 3 different phases, meal plans and recipes. The book is 384 pages long. The first section of this book was the best I have read since Dr. Walter Willett’s Eat, Drink and Be Healthy (a must read for those who have not read it yet). 

5 Things I Really Liked About Always Hungry
1) I really liked how Dr. Ludwig explains the hormonal consequences of the foods we eat. He presents a beautiful summary of the research to date on glycemic index and glycemic load and puts a serious hole in the theory that a calorie is a calorie. 

2) Finally, a popular weight loss book that talks about reasonable weight loss. Dr. Ludwig explains that good and steady weight loss is ½ pound to 2 pounds per week. So many people think that their weight loss plan is failing if they don’t lose 5 pounds a week and it is a shame. Slow and steady wins the race with weight loss. You need to give your body time to adjust to the weight you lose. In my opinion, this minimizes the level of “fight back” your body will give in terms of increased hunger and decreased metabolism.

3) I really agree with Dr. Ludwig when he says that refined carbohydrate and sugar consumption are the critical components of weight gain and need to be the focus of weight loss efforts. 

4) Dr. Ludwig recommends the reader consume a source of protein, fat, and low glycemic carb at each and every meal. The addition of the protein and fat attenuates the glycemic response. This will sound familiar to those who have read my book. This is probably because both Dr. Ludwig and I used the same research to formulate our weight loss strategies. This method of macronutrient combination just flat out works if you are trying to lose weight.

5) I also really like how Dr. Ludwig incorporates sleep and stress reduction into his program. These are two critical areas for those looking to lose weight that do not get nearly enough attention.

5 Things I Didn’t Agree With In Always Hungry
1) The book really didn’t stress the importance of resistance training, which I feel is mandatory if long term weight loss is your goal. Resistance training both increases metabolism and spares lean body mass during the weight loss process. 

2) I thought the cardio recommendations were a little on the light side. I have found that women in particular need to do a lot more cardio than Dr. Ludwig recommends in order to achieve and maintain their weight loss goals.

3) The program allows 2 alcohol containing drinks per day. While I can’t deny the health benefits of moderate alcohol consumption, in my clinical experience, this amount of alcohol will dramatically slow down the weight loss process.

4) In the food lists, there is no limit whatsoever on saturated fat and red meat. Foods like beef, full fat cheese, butter, sour cream, and heavy cream can be included at every meal if you want. I found this surprising. Many of these foods have been associated with an increased risk of heart disease, stroke and certain cancers and I don’t know why you would not want to focus on more healthful choices of protein and vegetable based fats.

5) The addition of up to 6 teaspoons of sugar each day and an ounce of 70% cocoa dark chocolate (which adds another 2 teaspoons) was surprising to me. The research Dr. Ludwig presents on the dangers of sugar and its addictive properties is very compelling in the first section. In my experience, the vast majority of those with a weight problem have uncontrollable cravings when consuming sugars and refined grains and they will not stop at just a few servings of these foods. The more sugar they have, the more they want. 

I do believe that there are people who are not addicted to sugar and refined carbs and can have just 1 cookie and stop there. These people are few in number and almost never have a problem with their weight. To me, the only answer is complete sugar restriction. After a 2 week withdrawal period, it is amazing how you won’t care that you are not eating sugar. I can’t think of a single client of mine that has attained their weight loss goal who ate sugar regularly. 

Is Always Hungry Worth Reading?
100% yes! I truly enjoyed this book. Many of my recommendations came from the same research that Dr. Ludwig covers in the first section of this great book. Our approach is very similar and we differ in just a few areas. I believe exercise should get a bit more attention. I believe that saturated fat and red meat should be limited. I believe sugar should be avoided 100%. Lastly, I believe that alcohol consumption should be a bit more controlled. This is an excellent book and a must read for anyone interested in how the food we eat can impact our weight and our health.

 

Friday, May 13, 2016

How much sleep do I need?

In the last few years, it has become evident that sleep deprivation has a negative impact on ability to lose weight. Although there is much left to learn about the mechanisms involved, it appears that at least 2 things happen to you when you do not get enough sleep:

1) Leptin levels drop. Leptin is a hormone that influences your metabolism. When leptin levels drop, you burn fewer calories.

2) Ghrelin levels increase. Ghrelin is a hormone that influences appetite. The higher the ghrelin, the more hungry you will be.

For obvious reasons, the combination of burning fewer calories and eating more because you are hungry makes it tough to lose weight.

Many studies over the last 10 years have shown a decreased metabolism and/or increased energy intake with sleep deprivation.

So, how much sleep do you need? Most studies show that 7 hours or more are what you are looking for. I have also found this to be true with my own clients.

Take a good look at your sleeping habits. Sleep deprivation can often be a little thought of, but very important component of your weight loss program.
 

Energy and macronutrient intake after gastric bypass surgery

The Study
Gastric bypass surgery is an effective strategy for weight loss in the severely obese when diet and exercise has not been effective. However, in most cases, 40-50% of lost weight is regained after several years and it is not clear why this is the case.

In this study, 16 women were followed for 3 years after bypass surgery. Total energy, lean body mass, and basal metabolic rate were measured at regular intervals during the follow-up. By the end of 12 months, the women had lost an average of 87 lbs.

At baseline, calorie consumption was 2,072 per day.

At 1 month post surgery, it dropped down to 681 calories.

At 12 months post surgery, it increased to 1240.

At 36 months, it increased to 1,448 calories.

As far as basal metabolic rate:

At baseline, it was 1.1 kcal/minute.

At 3 months it was .93 kcal/minute.

At 12 months it was .86 kcal/minute.

At 36 months is was .85 kcal/minute.

By the end of 1 month, 51.6% of weight lost was lean body mass. By the end of one year, 24.5% of weight lost was lean body mass. By the end of 36 months, 30% of weight lost was lean body mass. American Journal of Clinical Nutrition 2016; 103:18-24.

Take Home Message
This is a really important study, not just for those who have bypass surgery, but for everyone looking to keep lost weight off for good. Over the 3 years of this study, we saw a gradual increase in caloric consumption, a gradual decrease in basal metabolic rate, and a very significant loss in lean body mass.

Remember, lean body mass burns calories and is highly related to metabolism. You lose muscle, your metabolism drops and weight regain is far more likely. 

This study shows why a lot of people who get gastric bypass surgery regain their weight. They are the same reasons why the rest of us regain our weight; calories shoot back up and metabolism drops. 

The body may lower metabolism in response to weight loss. There is not much we can do about that. However, we can minimize loss of muscle mass by lifting weights consistently throughout the weight loss process and during weight maintenance. Keeping a close eye on caloric consumption is also essential to keeping the weight off.

This study would have been perfect if half the women were randomized to a weight lifting routine post surgery to compare basal metabolic rates and percent lean body mass lost.

Thursday, May 12, 2016

Probiotics and Weight Loss

The Study
Probiotics are live micro-organisms that have been shown to improve varying aspects of health when consumed in the proper quantities. It has been hypothesized that they increase rate of weight loss. In this randomized controlled trial, 89 overweight and obese women consumed a standard low fat yogurt, or a probiotic yogurt, for 12 weeks while following the same comprehensive weight loss program.

At the end of follow-up, women in both groups lost similar amounts of weight. However, the women consuming the probiotic yogurt had a 13.9 mg/dl drop in total cholesterol and a 13.5 mg/dl drop in LDL cholesterol when compared to the standard low fat yogurt group. They also had significant improvements in blood glucose and insulin levels. American Journal of Clinical Nutrition 2016; 103:323-29.

Take Home Message
This is a very nicely designed trial with a simple message. Probiotics can definitely improve certain health parameters but do not appear to increase the rate of weight loss. We are just beginning to learn about the health effects of the gut microbiota, but it appears to be an extremely important and complex element of good health. Unfortunately, it does not look like a quick fix for weight loss.