Saturday, July 13, 2019

Does skipping breakfast make it harder to lose weight?

The Study
For decades, people trying to lose weight have been told that skipping breakfast will seriously hurt their efforts. A recently published meta-analysis put this theory to the test. A meta-analysis combines the findings from several trials and produces a summary estimate of the results. This particular meta-analysis included 13 randomized trials. The results were both interesting and surprising. There was a slight weight loss benefit to skipping breakfast. Subjects randomized to a breakfast skipping group lost about 1 pound more than subjects randomized to a breakfast eating group. The breakfast skippers also had an average of 260 fewer calories consumed per day. British Medical Journal 2019; 346:142.

Take Home Message
Before we all start skipping breakfast, lets take a deep breath. While this study is interesting, the trials only lasted between 24 hours and 16 weeks. This is a very short time for weight loss studies. If there was a drop in resting metabolic rate with skipping breakfast, it may not appear until after this amount of time. In fact, this paper mentions that longer term observational studies have shown a weight loss benefit to eating breakfast.

Despite these interesting results, I still recommend eating breakfast for the following reasons:

-If you eat dinner at 6 in the evening, skip breakfast the next morning and have lunch at noon, you have gone 18 hours without food. My concern with this amount of time fasting is that your body will go into starvation mode and start to reduce resting metabolic rate. There is evidence in the research literature that fasting can decrease resting energy expenditure, as well as have a number of other effects that decrease weight loss efficacy. (Take a look at some of this research here)

-If you are only eating twice per day, it is really hard to get enough protein, healthy fats, fruits, vegetables, vitamins and minerals.

-Your mood, focus, energy and attention will be better if you eat breakfast. 

There are lots of good reasons to eat breakfast. Although this is a very interesting study, I wouldn’t let it change your mind about the importance of this meal.

Is snacking a good idea if you are trying to lose weight?

The Study
Many of my weight loss clients ask me if they are permitted to snack if they get hungry in between meals. A recent study published in the American Journal of Clinical Nutrition examined the impact of snacking on total daily calories. In this investigation, 3,777 men and women from the National Health and Nutrition Examination Survey were studied. These subjects each filled out two 24-hour dietary recalls. In one of the recalls, the subject reported snacking in between meals. In the other, they did not. Total calories were compared between the two days.

On the days that the men snacked, they consumed an extra 239 calories. The women consumed an extra 219 calories on the day that they snacked. Added sugars and sodium were significantly higher on the days that included snacking. American Journal of Clinical Nutrition 2019;109:1145-53.

Take Home Message
I have never been a big fan of snacking for my weight loss clients. If you are eating 3 good, blood sugar stabilizing meals each day, there is really no need to snack. You should not be at all hungry in between meals. The additional calories that snacking adds can have a dramatic impact on body weight. The 200 plus extra calories found in this study would result in nearly two pounds gained each month. 

Eat three balanced meals that include a healthy source of fat, protein and low glycemic carb. You won’t be hungry in between meals and it will be much easier to lose weight.

New research on eggs and cardiovascular disease

Eggs are back in the news in a big way after a meta-analysis published in April in the Journal of the American Medical Association showed an increased risk of cardiovascular disease with only ½ egg consumed per day. Should this study lead us to alter our consumption of eggs? Let’s take a closer look.

The Article
The meta-analysis included 29,615 participants from 6 prospective U.S. cohorts that were followed for roughly 18 years (Reference 1). Each additional half egg consumed per day was associated with a 6% higher risk of cardiovascular disease and an 8% higher risk of mortality.

Limitations And Other Research
While this is definitely an interesting study and we must consider the findings, there are two reasons not to go completely overboard and swear off eggs completely.

#1: There are some methodological issues with this study. To start with, only a single measure of egg consumption was taken and then subjects were followed for 18 years. There is a really good chance that egg consumption changed during this time. Very few of us eat the same way for 18 consecutive years. This study did not account for changes in diet over the follow-up.

Another methodological issue is that the control of confounders was not ideal. A confounder is a variable that may impact risk of cardiovascular disease. To deal with a confounder, you measure it and then control for it in statistical models. Similar to egg consumption, confounders in this study were not updated, just a baseline measure was used. This leaves the door open for residual confounding. Further, certain confounders were left out of the models, including family history of cardiovascular disease, menopausal status and supplement use.

#2: Other studies that were better executed do not show an increased risk of cardiovascular disease with a high consumption of eggs. For example, in an analysis of the Nurses’ Health Study and the Health Professional Follow-up Study that included 117,933 men and women, no significant association was found between consumption of one egg per day and risk of heart disease or stroke (Reference 2). In this study, both egg consumption and confounders were repeatedly updated during the follow-up period. There was also a more complete control of confounders.

Another very large meta-analysis was conducted a few years back (Reference 3). This analysis included subjects taken from 22 cohorts with a follow-up of up to 20 years. When comparing subjects who consumed one or more eggs per day to subjects consuming less than 1 egg per week, there was no increased risk of heart disease, stroke or total cardiovascular disease.

Conclusions And Recommendations
While the results of this new study need to be considered, a lot of other well-designed research has shown that eggs are safe to consume. If you are otherwise healthy, a moderate consumption of eggs can be considered part of a healthy diet. Keep in mind that eggs are a really good source of protein, healthy fat, vitamins and minerals. The yolks are very much like a multivitamin pill.

If you have diabetes, talk to your doctor about how many eggs you should consume, as some research has shown an increased risk of cardiovascular disease with high egg consumption in diabetics.

1) Zhong VW, et al. Association of dietary cholesterol or egg consumption with incident cardiovascular disease and mortality. Journal of the American Medical Association 2019; 321:1081-95.

2) Hu FB, et al. A prospective study of egg consumption and risk of cardiovascular disease in men and women. Journal of the American Medical Association 1999; 281:1387-94.

3) Shin, et al. Egg consumption in relation to risk of cardiovascular disease and diabetes: A systematic review and meta-analysis. American Journal of Clinical Nutrition 2013; 98:146-59.

Tuesday, May 14, 2019

Can I drink alcohol if I am trying to lose weight?

This is a question I get all the time from new clients.  The answer is yes you can, but in moderation. Alcohol has been associated with weight gain in the research literature. Scientists from Harvard combined subjects from 3 separate cohorts into a giant study on individual foods and weight gain (1). Over 120,000 men and women were followed for up to 20 years. Increases in alcohol, even just one drink a day, were significantly and consistently associated with modest weight gain. There are several reasons why this may be true:

-Alcohol is calorie dense, it contains 7 calories per gram. A typical beer has 150 calories, a glass of wine has 85 calories and 1.5 ounces of hard liquor generally has 100 calories. Have 2 or 3 of these a day and trust me, the calories begin to add up.

- Liquid calories generally don’t register with the body. In other words, if you eat a solid food snack in the late afternoon, you would compensate by eating a little less at dinner. The body does not seem to recognize liquid calories in the same way. So, if you have a drink or two before dinner, you don’t eat any less food. In this way, alcohol calories are simply added on rather than substituted.

               - Alcohol can’t be stored in the body, so it becomes a priority for oxidation. Because of this fact, alcohol consumption suppresses fat oxidation. Therefore, you are burning less of your body fat when you drink.

               - In my experience and that of my clients, when you have a few drinks and start to get a bit of a buzz, your discipline goes out the window. After 3 or 4 drinks, the dessert menu becomes harder to resist and the late night fast food/diner stop seems to become all but inevitable!

You don’t necessarily have to give up alcohol here. If you have a few drinks a week, say four or less, you’ll be fine. If you’re drinking every day, this can really slow your rate of weight loss. A good strategy that several of my successful clients have used is to drink only on the weekends and avoid alcohol completely during the week.

1) Mozaffarian D, et al. Changes in diet and lifestyle and long-term weight gain in women and men. New England Journal of Medicine 2011; 364:2392-404.

Multivitamin use and your health

The Study
The health benefits of multivitamin use remain controversial. In this recent investigation, 30,899 adults identified through the National Health and Nutrition Examination Survey (NHANES) had their multivitamin use measured and then were followed for over 6 years. Multivitamin use had no association with risk of mortality in either direction. A few other interesting findings:

-Adequate intake of Vitamin A, K, magnesium, zinc and copper were associated with a reduce risk of all cause mortality. However, this was only true when these nutrients were obtained from foods, not from supplements.

-Excess intake of calcium was associated with an increased risk of cancer death. This association was mostly from supplemental calcium, not calcium obtained from food.

Annals of Internal Medicine doi:10.7326/M18-2478

Take Home Message
It appears that multivitamins don’t do much harm or much good. There really is no reason to take them. I always recommend getting your vitamins and minerals from your food. Make sure to include a variety of fruits and vegetables, whole grains, and nuts each day. The findings concerning calcium are disturbing. If you are taking a high dose of calcium, you may want to talk to your doctor about the pro’s and con’s of doing so.

Monday, May 13, 2019

Fruits And Vegetables And Your Health

The Study
Blood levels of vitamin C, carotenoids and alpha-tocopherol are biomarkers for fruit and vegetable consumption. In a meta-analysis of 69 prospective cohort studies, the association between these biomarkers and health were examined. In addition to blood levels, this study also examined dietary intake of these nutrients. The results were impressive. Blood levels/and or dietary intake of these nutrients were associated with a statistically significant lower risk of coronary heart disease, stroke, cardiovascular disease, cancer and all-cause mortality. American Journal of Clinical Nutrition 2018: 108: 1069-91.

Take Home Message
We have all heard it many times before- fruits and vegetables are good for you. Well, they still are. Fruits and vegetables are among the most healthy things that we can eat. Load up on them. I have my clients shoot for at least 5 servings per day of fruits and vegetables. More is better. 

Just a few notes:

-Limit dried fruits, like raisins and dried cranberries. These are higher glycemic can spike your blood sugar.

-Limit fruit and vegetable juices. These are also high glycemic.

-Try to vary your sources of fruits and vegetables. Get as many colors on your plate as possible.

Product Review: Lose it! Food Tracking App

If you are trying to drop a few pounds, keeping track of what you are eating is essential. It provides accountability and gives you a sense of control over the healthy changes you are trying to make. I always have a new client write down their food for the critical first few weeks of our work together. 

That is why the Lose it! app is next up for review. This is an app for your smart phone that allows you to track your food. It is available for both Android and iPhones.

1) The lite version is free, which is great. 

2) It is really easy to use. It takes about 2 minutes to get comfortable with how it works.

3) There are 7 million foods in the database. Every single food I tried to look up was there.

4) It is convenient. Being able to log your food on your phone makes it really easy.

5) There is a macronutrient breakdown that shows you the percentage of your diet that is fat, protein and carbohydrate. This is very useful.

6) You can scan the bar code of a food item in the app to add it to your meal. This really increases the accuracy of your logging.

1) There are constant reminders to upgrade to the premium version. I don’t begrudge anyone trying to make money, but it does get a little annoying.

2) There is not a lot of nutrition information available in the lite version. Nutrients such as saturated fat, grams of sugar, sodium, etc, are not available.

3) There are lots of links to other things you don’t really need that clutter up the interface.

Do I Recommend the Lose it! food tracking app?
Absolutely. This is a great app that will help you keep track of your diet. It is convenient, free, easy to use and has a comprehensive food database. Lose it! makes logging your diet a snap. I do not know if upgrading to the premium version is a good value as I, personally, did not see the need to do that. Give this one a try. It is available at the Google Play Store or the App Store for Apple products.

Disclosure: I am not affiliated with the company that makes the Lose it! food tracking app and make no money if you use it.