Friday, January 13, 2017

What are some tips to get back on track with my diet after the holidays?

The time between Thanksgiving and New Years day presents some real challenges for those trying to eat healthy and lose weight. The holidays are great and it is a lot of fun celebrating with friends, families and coworkers. Just about everyone puts on a few pounds during this time and that is OK.

However, for many of us, the unhealthy eating continues well into January and even February. This is mostly due to swings in blood sugar that result in increased hunger and cravings for refined carbohydrates, which were likely consumed in large amounts over the last several weeks. The more we eat bread, pasta, white rice and sugar, the more we want these foods.

A couple of extra cheat meals and a few pounds gained during the holiday season are not much of a problem. But if the disordered eating lasts for months, you will put on some serious weight. Even my most successful and dedicated clients will struggle during and after the holidays. Here are a few strategies that help them get back on track:

1) If you have eaten more refined carbohydrates during the holiday season, you will have an increase in cravings for them. You will also be more hungry in general. Step one is to mentally realize this. Tell yourself that you will be hungry for the wrong foods, but will not give into them. Getting your head right and understanding the origin of the cravings is very helpful.

2) Write down your food for 2 weeks. It adds a layer of accountability that gets you back on the right track.

3) Go to the grocery store and load up on all of the right foods. Make it easy to eat healthy. 

4) Plan your meals ahead of time. Think about what you will eat for breakfast, lunch and dinner for the next few days or even a week.

5) Try to limit eating out at restaurants for the first week or two. The warm bread at the table and the menu with a million unhealthy options can be too much when you are craving the wrong foods. 

After a week or two of eating right, you will find that your blood sugar has stabilized and the hunger and cravings for the wrong foods will start to calm down.


Are low fat diets the best option for sustained weight loss?

The Study
Some of the most accomplished professors at Harvard University’s Department of Nutrition conducted a systematic review of weight loss trials to determine if low fat diets increased rate of weight loss compared to other approaches. After comprehensively evaluating the literature, 53 studies were identified that included over 68,000 participants. The findings were very interesting:

-In weight loss trials, low carbohydrate interventions led to significantly greater weight loss than low fat interventions (a difference of about 2.5 lbs.).

-Low fat diets did not lead to a difference in weight change when compared to higher fat weight loss approaches.

-In weight loss trials, higher fat diets led to significantly greater weight loss than low fat diets when groups differed by more than 5% of calories obtained from fat at follow-up (a difference of about 2.5 lbs). The Lancet 2015; 12:968-79.

Take Home Message
Despite decades of advice to the contrary, low fat diets really are not the best strategy for weight loss. There are a few reasons why dieters struggle with a low fat approach:

1) Since protein tends to stay relatively constant in most dieters, when they decrease fat, they increase carbohydrate consumption. In the American diet, this usually means more refined carbohydrates. Since fat acts to stabilize the blood sugar, the low fat, high carbohydrate pattern of eating causes a reactive hypoglycemia in many people that leaves them hungry. Over time, this hunger wins out and the dieter ends up snacking and overeating.

2) These swings in blood sugar also promote higher than normal insulin levels. There is evidence that higher insulin levels promote fat storage through a variety of mechanisms. 

Therefore, for many who attempt a low fat approach to weight loss, they are hungry, eating more, and storing fat at a higher rate. Not a good combination!

While there are certainly people that will do very well on a low fat diet, the research shows that for the typical person trying to lose weight, there are better options.

In both my analysis of the literature and my clinical practice, I have found the Mediterranean approach to be much more effective. This is a moderate fat, moderate carb, low glycemic load diet that stabilizes blood sugar and dramatically decreases hunger. My clients do amazingly well with this approach to weight loss.

Does exercising in the fasted state prevent weight gain?

The Study
Twenty-seven healthy male volunteers were overfed 30% of their body’s calorie needs for 6 weeks. During this overfeeding period, the men were randomized into one of three groups. Group #1 exercised early in the morning, before eating any breakfast. Group #2 ingested carbohydrate before and during their morning exercise. Group #3 was a control group that did not exercise. The two groups that exercised trained with identical programs (360 minutes of cycling and running per week). At the end of the 6 weeks, the control group gained 6.6 lbs. The group that exercised after breakfast gained 3.1 lbs. The group that exercised in the fasting state gained only 1.5 lbs. Journal of Physiology 2010; 588.21: 4289-4302.

Take Home Message
This is a very interesting study suggesting that exercising on an empty stomach may somehow protect us from weight gain. However, there is a major problem with this study that prevents us from drawing this conclusion with confidence. The study does not accurately measure, and does not provide for the reader, the number of calories these subjects consumed each day. The text of the article mentions that the energy intake in all groups was similar. This statement simply means that they were not significantly different statistically. It does not mean they were identical.

The difference in weight gain between the two groups was 1.6 pounds over 6 weeks, which equates to 133 calories per day. It may just be that the fasting group ate a tiny bit less than the breakfast group. The problem is that we don’t know what the difference was in calories per day. Therefore, it is impossible to conclude that exercising on an empty stomach has an impact on weight gain. However, this study has certainly generated an interesting hypothesis that should be tested with an intervention more sensitive to the caloric consumption of the participants. At the very least, this study shows us that exercising for an hour a day helps to prevent weight gain when overeating.

Book Review: Dr. Gundry's Diet Evolution

Next up for review is Dr. Gundry’s Diet Evolution. The author, Dr. Stephen Gundry, is a heart surgeon who has pioneered the development of several surgical devices and techniques. He is a very accomplished physician.

This interesting book presents a weight loss strategy based on an understanding of how our genes work. Dr. Gundry believes that over many thousands of years, our genes have developed defense mechanisms that are now working against us when it comes to our weight and our health. His theory is that by adopting certain dietary and lifestyle habits, we can make these genes work for us instead of against us, resulting in weight loss and improved health. The book is 304 pages long. It is well written and I enjoyed reading it.

5 Things I Really Liked About Diet Evolution
1) It strictly limits sugar and refined carbohydrates like white bread, white rice and pasta. In my opinion, limiting these foods and stabilizing your blood sugar are pivotal to improving your weight and your health.

2) It allows cheat meals. This is a huge part of my recommendations as well. I find regular cheat meals to be essential for several reasons: 1) You don’t have to be perfect to get really good results. 2) The idea of never having a piece of bread, a slice of pizza or a burger again in your life is not at all realistic. 3) Sometimes it is just fun and appropriate to eat junk food. If I am at a Jets or Islanders game, it just does not feel right to be eating a salad or a bowl of black beans.

3) I really like how Dr. Gundry promotes slow and steady weight loss. A huge problem with most weight loss books is that they promise a ridiculous, unsustainable rate of weight loss. A pound a week is what you are looking for. It may not be fast, but it is sustainable and realistic. It is also my opinion that losing weight slowly gives you a much better chance of keeping it off.

4) I like that Dr. Gundry recommends resistance training for weight loss. It is always surprising to me how many weight loss books do not include this essential component.

5) The book contains a large number of well put together recipes.

5 Things I Didn’t Agree With In Diet Evolution
1) This book has a lot of restrictions on what I consider to be very healthy foods. For example, all of the following are considered “Unfriendly” foods and are restricted to some degree: carrots, peas, sweet potatoes, squash, mangos, pineapple, pears, legumes, oatmeal, quinoa, etc. These are all healthy foods I recommend to my clients and I’m not quite sure why they are considered so bad for you on this program.

2) Diet Evolution makes a number of claims that are not supported by the research literature: Here is a small sample:

Eating legumes will slow the rate of weight loss.

Eating whole grains will slow the rate of weight loss.

Milk causes cancer.

Low fat diets have shown to be the most successful for weight loss.

3) The book spends a good amount of time explaining why non-nutritive sweeteners are to be avoided, but includes them in a very large percentage of the recipes.

4) I was really surprised that Dr. Gundry dispels all prospective cohort studies as “silly observations”. I understand that only randomized trials can prove cause and effect. However, they have some very serious limitations when it comes to diet and lifestyle research. For example, ethical issues, short length of follow-up, high drop out rates and low compliance plague most trials concerning our diet and lifestyle. 

In most cases of lifestyle research, longer term cohort studies will give us our best chance of answering our research question. Here is an example; there has never been a single randomized trial to test if cigarette smoking causes lung cancer. Ethical considerations rightfully prevent any such trial from being conducted. However, observational research has consistently shown that smoking causes lung cancer. This is not a silly observation to me! I also found it ironic that later in the book, when discussing the benefits of moderate alcohol consumption, Gundry backs up his claim by citing a reference on alcohol consumption and risk of coronary heart disease in the Health Professional Follow-up study, which happens to be a prospective cohort study.

5) This book is very heavy on vitamin and mineral supplementation. In my opinion, the research has not shown such supplementation to be beneficial and in some cases, it can even cause harm. It never makes sense to me when a dietary program strips a lot of healthy foods out of the diet (such as fruits, legumes, whole grains, etc) and then suggests vitamin and mineral supplementation to fill in the nutritional gaps. Why not just leave the nutrient packed foods in the diet? To me, any diet that we need to supplement with pills to balance our nutrient needs is not a natural diet for humans to consume.

Is Diet Evolution Worth Reading?
Absolutely. This book gets a lot right and the theory of how our genes impact our food choices is a unique take and quite interesting. I would just ease the restrictions on what I consider to be healthy foods such as fruits, vegetables, legumes, whole grains, lean sources of protein and healthy fats.

Monday, November 14, 2016

Raisins are a convenient and portable way to get my fruit, right?

As a derivative of fruit, it makes sense that most people think of raisins as a healthy food. My clients are usually quite surprised when I tell them that dried fruit needs to be strictly limited.

The problem with raisins arises during the drying process. Drying a fruit increases the sugar content dramatically and decreases the fiber. 

As you probably know, raisins are dried grapes. A serving of grapes (4 ounces) has a glycemic index of 43 and a glycemic load of 7, both of which are on the lower end (Reference 1). However, a serving of raisins (2 ounces) has a glycemic index of 64 and a glycemic load of 28, both on the high end (Reference 1).

The key to eating for weight loss is to maintain a stable blood sugar. This strategy helps to keep insulin at a reasonable level and significantly reduces hunger and subsequent energy intake.

Despite having some nutritional upside, eating raisins is very similar to eating candy when it comes to your blood sugar. If you are trying to lose weight, a much better choice is to go for fruit in its whole and natural form.


Religious service attendance and mortality

The Study
Over 74,000 women in the Nurses’ Health Study had their religious service attendance assessed repeatedly by questionnaire and were followed for 20 years. By the end of follow-up, women who attended religious services more than once per week had a statistically significant 33% lower rate of mortality when compared to women who did not attend religious services. The association held after controlling for all known predictors of death in this cohort. JAMA Internal Medicine 2016; 176:777-85

Take Home Message
This is a fascinating study to me. You don’t see a lot of literature on the subject of religious beliefs and health outcomes, but the reduction in risk of mortality in this investigation is strong and impressive.   

The mechanism for the reduction in risk of death in the religious is not known. However, the authors suggest several possibilities:

 1) Increased social support

2) Lower levels of depression

3) Higher levels of optimism

4) Religious coping mechanisms

5) More purpose in life

6) More self discipline

7) Higher psycho-social resilience

It is certainly beyond the scope of this blog to make recommendations of a religious nature. However, I just wanted all of my readers to be aware of this association, because it appears to be a very important predictor of long-term health.

Can lifting light weights effectively build muscle?

The Study
In this study, 49 men that lifted weights regularly performed 12 weeks of resistance training. The men were randomly allocated to one of two training groups; the first group used very heavy weights (75-90% of 1 rep max) for 8-12 repetitions per set, the second group used much lighter weights (30-50% of 1 rep max) for 20-25 repetitions per set. Each group lifted weights 4 times per week. At the end of follow-up, there were significant increases in muscle mass in both groups with no difference between groups. Journal of Applied Physiology 2016; 121:129-138.

Take Home Message
This study shows that you don’t have to lift very heavy weights in order to build muscle. You can get similar increases in muscle mass with lighter weights and higher repetitions. I use lighter loads with most of my clients, for a bunch of reasons: 1) I find there is a lower risk of injury. 2) It is my opinion that it is safer (lower spikes in blood pressure and heart rate) than using much heavier weights. 3) I find there is a lower risk of overtraining with lighter weights. 4) Generally, it is more enjoyable. Experienced weight lifters actually enjoy the fatigue and “burn” that comes with lifting heavy weights. Most people that are new to weight lifting and that are deconditioned do not. 

This study shows us that you can build muscle quite well with lighter loads, as long as you increase your repetitions.