Saturday, September 15, 2018

Benefits of fasting for active people goes beyond weight loss

Although intermittent fasting starting making news in 2016 and really became popular in 2017, researchers began considering the effectiveness of fasting a decade earlier.  Dr. Mark Mattson has studied in the connection between nutrition and diseases such as Alzheimers for quite a while.  He is the chief of the Laboratory of Neurosciences at the National Institute of Aging and Professor at Johns Hopkins.  His research influenced Dr. Michael Moseley, who did a BBC documentary in 2012 about the benefits of intermittent fasting.

I became more curious about Mattson after reading Kyle Boelte's May 2017 article in Outside Online entitled "What I Learned from a Year of Intermittent Fasting."  Boelte is an active man in his 30s who does not need to worry about losing weight.  However, he tried fasting to address issues that were compromising the quality of his life.  The subtitle for the article is "It won't solve all your health problems, but it might make your life a bit better."  In Nov 2017, he wrote a followup article entitled "How to Start Fasting: A beginner's guide to the burgeoning nutrition trend" that is also a good read.  It's the best introduction I've found so far for active people willing to experiment with fasting.
"I settled on the 16-hour fast, where I’d limit eating to an eight-hour window every day. As Mattson explains, the liver stores glucose (the body’s main energy source when you are regularly eating carbohydrates) for about ten to 12 hours after a meal. When you fast for more than 12 hours, your body switches from glucose metabolism to fat metabolism, which leads to a bunch of positive adaptive cellular stress responses. So, if you fast for 16 hours each day, you’re receiving the benefits of those adaptive responses without limiting your total caloric intake." 
https://www.outsideonline.com/2181151/what-i-learned-year-intermittent-fasting 
https://www.outsideonline.com/2258396/how-start-fasting

The 2014 medical journal article by Dr. Mattson referenced in Outside Online is entitled "Meal frequency and timing in health and disease."  There is a long list of references for those interested in learning more.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4250148/
Proc Natl Acad Sci U S A. 2014 Nov 25; 111(47): 16647–16653. 
Published online 2014 Nov 17. doi:  10.1073/pnas.1413965111

Thursday, September 13, 2018

Reasons to avoid diet soda

The idea that diet soda is "healthy" seems to be more a function of good marketing since the 1960s than any scientific research.  The same could be said of sugar substitutes in general, but those who drink diet soda regularly probably consume far more soda than other food with the same amount of sugar substitutes.  The negative impact of drinking 1+ diet sodas per day in the U.S. is not new information.  However, the long term impact from an epidemiological standpoint is probably more obvious in 2018 than it was fifty years ago when diet drinks were still relatively new.  Coca-Cola and Pepsi were selling diet sodas by 1963.

A search on "reasons not to drink diet soda" will bring up lots of articles.  Here are a few to think about.



includes links to references - 2018

Looking for clinical trials related to diet soda can get pretty complicated.  Here's an example.  This 2015 study from the American Journal of Clinical Nutrition compared diet soda to water over a 24-week period.  It's a small study considering obese women with about 30 subjects in each group.  The soda group drank 1 soda at lunch 5 days a week.  The results was that the group drinking water at lunch lost more weight and the difference was statistically significant.  The level of insulin resistance was also measured and the water group did better.

Effects on weight loss in adults of replacing diet beverages with water during a hypoenergetic diet: a randomized, 24-wk clinical trial

It's clear that a diet soda causes just as much of an insulin spike as a regular soda.  Higher insulin levels means less chance the body switches over to burn stored fat.  That can be a key reason people who drink diet soda all day long have big waistlines and trouble staying at a healthy weight, no matter how much they restrict calorie intake and/or exercise.

The development of diabetes, kidney failure, heart failure, or osteoporosis takes years and there are many risk factors.  The research in the last 10-20 years generally supports the idea that finding an alternative to diet soda that does not include sugar substitutes is worthwhile for people interested in long term health.

When I was growing up, my family never drank soda of any kind.  Now that I am over sixty, I am rather glad I do not like soda or the taste of any sugar substitute in any type of drinks.

Science behind fasting, hunger, and daily eating habits

As I looked around for information about fasting, I came across a series of well researched videos by an American living in Tokyo in a blog called What I've Learned.  Some of the videos go together with a blog entry of the complete text.  My interest in learning more about fasting is in longevity with a high quality of life, as opposed to any need to lose more than a few pounds.

The 2018 video below is a good summary of about why someone who is fasting does not feel hungry all the time.  There are several hormones involved with eating and how the body finds fuel from food or stored fat that have only been measured relatively recently as part of medical research.  An example of of Ghrelin (hunger hormone) levels during fasting begins at the 5 min. mark.  Note that 2017 book The Obesity Code by Dr. Jason Fung is referenced.

The 2016 video about eating one meal per day includes references that demonstrate that the idea of fasting as beneficial are not particularly new.  What's actually new in the history of human beings is the concept that three meals a day are necessary for a healthy lifestyle.

Intermittent Fasting & Hunger - What the Science says, 11 min - 2018
https://www.patreon.com/posts/16239257
https://youtu.be/dFT2IKmwyfg



Longevity & Why I eat once a day, 16 min - 2016
https://lifeforbusypeople.com/2016/07/23/longevity-why-i-eat-once-a-day/
https://youtu.be/PKfR6bAXr-c