By Jey McCreight, Scientist, Research Communications
Most New Year’s weight loss resolutions fail even with the best of intentions – but what if people had a helping hand?
According to 23andMe research, many people reported making healthy changes to their lifestyle after receiving personalized genetic reports with information about diet and weight.
We know this from the data we’ve gathered from our customers who viewed our Saturated Fat and Weight Report. This report, launched in the summer of 2016, looks specifically at how the interaction between saturated fat intake and the rs5082 genotype impacts body mass index, BMI. Those with the GG genotype are likely to weigh more on diets high in saturated fat, and are told that their genetics may make limiting saturated fat intake especially important for maintaining a healthy weight. Because limiting saturated fat intake may also be important for reducing the risk of heart disease1, the report encourages all customers to do so, regardless of their genetic results. <img loading="lazy" decoding="async" class="alignleft wp-image-25967 size-large" src="http://35.88.189.111/wp-content/uploads/2018/01/rs5082_geno_distrib-1024x281.png" alt="" width="1024" height="281" srcset="https://blogcms.23andme.com/wp-content/uploads/2018/01/rs5082_geno_distrib-1024x281.png 1024w, https://blogcms.23andme.com/wp-content/uploads/2018/01/rs5082_geno_distrib-300x82.png 300w, https://blogcms.23andme.com/wp-content/uploads/2018/01/rs5082_geno_distrib-768x211.png 768w, https://blogcms.23andme.com/wp-content/uploads/2018/01/rs5082_geno_distrib-880x241.png 880w, https://blogcms.23andme.com/wp-content/uploads/2018/01/rs5082_geno_distrib.png 1116w" sizes="auto, (max-width: 1024px) 100vw, 1024px" />
What we learned is that one month after viewing the Saturated Fat and Weight Report, many participants reported making changes to their diets – and the news was even better six months later.
One month after viewing the report, we asked research participants about their plans to make dietary changes. While about half of participants said they hadn’t considered changing what they eat, some said they had already started to make dietary changes (20%), planned to make changes (10%), or at least considered making changes (17%).
Six months later, the same participants answered another survey about dietary changes in this time period. Of those who had initially reported that they had already started to change what they eat, 82% were still maintaining those dietary changes. 80% of participants who had planned to make changes followed through with those plans, and 60% of participants who considered making changes ended up doing so. Even among participants who had not given it much thought originally, 31% ultimately made healthy dietary changes.
<img loading="lazy" decoding="async" class="alignleft wp-image-25971 size-full" src="http://35.88.189.111/wp-content/uploads/2018/01/fig5_laskey_v2.png" alt="" width="916" height="596" srcset="https://blogcms.23andme.com/wp-content/uploads/2018/01/fig5_laskey_v2.png 916w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig5_laskey_v2-300x195.png 300w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig5_laskey_v2-768x500.png 768w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig5_laskey_v2-880x573.png 880w" sizes="auto, (max-width: 916px) 100vw, 916px" />Those dietary changes were in line with what the Saturated Fat and Weight Report suggested: decrease saturated fat intake, and correspondingly increase unsaturated fat intake.
<img loading="lazy" decoding="async" class="alignleft wp-image-25963 size-large" src="http://35.88.189.111/wp-content/uploads/2018/01/fig3_laskey-1024x540.png" alt="" width="1024" height="540" srcset="https://blogcms.23andme.com/wp-content/uploads/2018/01/fig3_laskey-1024x540.png 1024w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig3_laskey-300x158.png 300w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig3_laskey-768x405.png 768w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig3_laskey-880x464.png 880w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig3_laskey-1180x622.png 1180w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig3_laskey.png 1320w" sizes="auto, (max-width: 1024px) 100vw, 1024px" />Additionally, reduced saturated fat intake was significantly associated with BMI category (p = 3 x 10-44) and genotype (p = 5 x 10-12) as evaluated by a chi-squared test. This suggests that providing personalized results &#8211; in this case, the gene-by-environment interaction between rs5082 genotype and dietary saturated fat intake &#8211; can encourage people to make healthy lifestyle changes.
<img loading="lazy" decoding="async" class="alignleft wp-image-25965 size-full" src="http://35.88.189.111/wp-content/uploads/2018/01/fig5_laskey_v2_p1.png" alt="" width="916" height="308" srcset="https://blogcms.23andme.com/wp-content/uploads/2018/01/fig5_laskey_v2_p1.png 916w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig5_laskey_v2_p1-300x101.png 300w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig5_laskey_v2_p1-768x258.png 768w, https://blogcms.23andme.com/wp-content/uploads/2018/01/fig5_laskey_v2_p1-880x296.png 880w" sizes="auto, (max-width: 916px) 100vw, 916px" />Like any study, these findings may not be generalizable to other populations. Survey questions nonrandomly targeted only people who said they had viewed the report. Respondents were also disproportionately female, and female respondents were slightly more likely to report making changes in response to the Saturated Fat and Weight Report. Finally, given the sensitivities that surround the topic of diet and weight loss, this study may be subject to <a href="https://en.wikipedia.org/wiki/Social_desirability_bias">social desirability bias</a> &#8211; the tendency of respondents to answer inaccurately in order to present themselves favorably &#8211; as there were no direct measurements of dietary intake.
We believe that the results presented here support the need for ongoing research looking at the effectiveness of personalized genetic results as a motivator for positive lifestyle change. Although there are limitations, it appears that simply receiving the report may have motivated healthy changes for some people of all genotypes, with the effect being even stronger for those with the GG genotype.“It&#8217;s nice to know that there&#8217;s a big population out there of engaged, excited customers who want to make healthy changes,” says study lead Sarah Laskey, PhD, Health R&amp;D Scientist at 23andMe. “This is what&#8217;s so exciting about our new Weight Loss Intervention study &#8212; hopefully that enthusiasm will enable us to make big strides in the science of genetics and weight loss!”
For more details, <a href="https://blog-api.23andme.com/wp-content/uploads/2017/10/23andMe_ASHG_2017_Sarah.pdf">check out Sarah’s poster</a> from the 2017 American Society of Human Genetics annual meeting.
[1] <a href="https://www.ncbi.nlm.nih.gov/pubmed/26068959">Hooper L et al. (2015). “Reduction in saturated fat intake for cardiovascular disease.” Cochrane Database Syst Rev. 6:CD011737</a>

23andMe Blog

23andMe Blog Team

Tipping the scales: Participants make healthy dietary changes in response to direct-to-consumer genetic test results

Editor&#8217;s Note: This post was first published in 2017. It&#8217;s been slightly edited.
Just in time for New Year’s resolutions, 23andMe is embarking on a first-of-its-kind study that will engage with customers to learn more about genetic variants associated with weight loss and the effectiveness of using different diets or exercise to lose weight.
<h2>New Weight Loss Study</h2>
23andMe’s new “Weight Loss Intervention Study” will attempt to uncover more about why each of us responds differently to exercise and diet.  While scientists know that a person’s weight is determined by a complex combination of lifestyle, environment, and genetics, the interplay of those influences is still poorly understood.
“We’d like to better understand the genetic, demographic, psychosocial, and behavioral characteristics that predict weight loss success overall and on different lifestyle interventions,” said Liana Del Gobbo, Ph.D., 23andMe’s lead scientist on the study.
“This will help us begin to pave the way towards more personalized lifestyle recommendations.”
<h2><img loading="lazy" decoding="async" class="size-medium wp-image-25181 alignright" src="https://blog-api.23andme.com/wp-content/uploads/2017/03/weight-300x300.png" alt="" width="300" height="300" />Intervention Study</h2>
The size of this intervention—involving 100,000 eligible customers and examining three different weight loss strategies—is unprecedented, and no one has attempted a genome-wide association study of behavioral weight loss.
Although genetic association studies have focused on weight, specifically body mass index (BMI), no trials have looked at behavioral weight loss. This is important because the genetic variants that influence BMI may differ from those that affect weight loss. Also, for this kind of genome-wide association study to be effective, many people must participate in uncovering genetic variants. That is what makes 23andMe uniquely able to conduct this research now.
And the time to do this kind of work is right. Obesity is reaching epidemic levels with dire public health consequences. That, combined with the difficulty of losing weight—most people who try to lose weight fail, and even those who succeed in losing a few pounds often gain them back—makes gaining new insights into the genetics and behaviors leading to weight loss that much more important.
<h2>Genetic Weight Report</h2>
The study also comes less than a year after 23andMe launched its Genetic Weight Report, which combines large-scale genetic and non-genetic data with machine learning to provide personalized portraits of how genetics and lifestyle impact weight.
This study builds on the work that went into that report. For this research, participants will be recruited from a group of over a million 23andMe customers who consented to research and are potentially eligible to participate. To be eligible, participants must be 23andMe customers, overweight, but in good health, between 18 and 70. There are also other additional eligibility requirements. Recruitment for the study closes in early January, and then over 12 weeks, participants will follow one of three different interventions.
Participants will hear from researchers every other week via emails to help them through the study, offering weight loss advice, meal suggestions, and live researcher forums for support and updates. Within a few weeks of the study completion, researchers will report back to customers some of what we’ve learned. There will be another follow up with participants six months and then again a year later.
“Ultimately, we’d like to learn how to make traditional lifestyle interventions more scalable and cost-effective. This intervention will be an exciting first step,” said Liana.

23andMe Launches Landmark Weight Loss Study

By Nick Furlotte and Shirley Wu
For many of us, the battle of the bulge is more like an all-out war.
We all know people who can eat whatever they want, not work out, and yet not gain a pound. Meanwhile, eating just one burger, or missing just one cardio session, can weigh much more heavily on others (pun intended).  No doubt many of the differences we observe in weight gain and its relation to food intake and exercise are due to genetics.<img loading="lazy" decoding="async" class="alignright size-medium wp-image-19018" src="https://blog-api.23andme.com/wp-content/uploads/2013/08/Scale-300x282.jpg" alt="Scale" width="300" height="282" srcset="https://blogcms.23andme.com/wp-content/uploads/2013/08/Scale-300x282.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2013/08/Scale.jpg 357w" sizes="auto, (max-width: 300px) 100vw, 300px" />
At 23andMe we are very interested in identifying the genetic components that contribute to these differences between individuals. So we assessed people’s food and exercise habits, their physical characteristics (like whether they are “apple” or “pear” shaped), and we compared these answers to genetic data for tens of thousands of customers with European ancestry.
<h6>How do fast food and exercise affect weight on average?*</h6>
In our customers, a man of average height (5’9), average age (35) and European ancestry weighs about 180 pounds (corresponding to a body mass index (BMI) of 26.5, lower than the<img loading="lazy" decoding="async" class="alignright size-medium wp-image-19022" src="https://blog-api.23andme.com/wp-content/uploads/2013/08/WeightByGRS-female-300x195.jpg" alt="WeightByGRS-female" width="300" height="195" srcset="https://blogcms.23andme.com/wp-content/uploads/2013/08/WeightByGRS-female-300x195.jpg 300w, https://blogcms.23andme.com/wp-content/uploads/2013/08/WeightByGRS-female.jpg 631w" sizes="auto, (max-width: 300px) 100vw, 300px" />
The story is similar for the average height and average aged woman (5’4 and 35 years old) with European ancestry, who weighs about 145 pounds (a BMI of 24.8, much lower than the U.S. average of 29).  She will weigh about eight pounds less if she exercises once or twice a week, but will weigh three pounds more if she also eats fast food once or twice a week.
<h6>Why you should care if you’re apple or pear</h6>
None of this is surprising — exercise leads to lower weight on average while eating fast food leads to higher weight on average.  But it turns out that body type makes a difference.
In our customers, men with pear and apple body types weighed more if they ate fast food occasionally while men with a neutral body type weighed less with the same fast food intake. For women, having an apple shape is associated with a higher average weight (around 155 pounds) but there is very little difference in weight due to occasional fast food intake between the different body types.
Just don’t go overboard: women who ate fast food nearly every day tended to weigh about 20 pounds more than the average, and this went up by an additional six pounds for women with apple or pear shapes.
<h6>More reason to exercise</h6>
We all burn calories while we’re just sitting around, but wouldn’t it be great if you could burn more? It all depends on your “metabolic rate”, or how much energy (calories) your body uses while resting, and you can actually increase your metabolic rate by exercising regularly.
In 23andMe customers, we see this play out in the fact that physical activity level affects the degree to which fast food consumption impacts weight.  For example, an average man who eats fast food once or twice a week who also works out five to seven times a week weighs five pounds less than a man eating the same amount of fast food who does not work out at all. The story is similar for women: eating fast food and not exercising is associated with weighing 10 pounds more than average, while those who ate the same amount of fast food but also exercised frequently weighed only seven pounds more.
Of course, the difference in weight might not be due just to exercise frequency. People who exercise might also be doing other things that lead to lower weight, including eating a healthier diet overall. But the fact that exercise raises the metabolic rate makes it a plausible explanation.
<h6>Adding genetics to the picture</h6>
So how do our genetics influence all of this?    We know that certain genetic factors predispose to obesity while others may protect against it. But a recent study published in<a href="http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1003607"> PLOS Genetics</a> adds a twist. The researchers showed that a set of 12 genetic factors known to be associated with obesity had less of an effect in people who exercised more and a larger effect in people who did not exercise as often.
We examined the same idea using the data from our customers and found similar results.  In women who do not exercise, the genetic risk factors were associated with weighing 1.4 pounds more than average, while women who exercised weighed only 0.75 pounds more for each risk factor.  In other words, lifestyle may actually influence the effect our DNA has on our weight.
As the size of the weight loss industry attests, weight and obesity are very challenging problems. But with more data, we’ll be able to unravel the relationship between food intake, exercise, genetics, and weight gain even more, hopefully leading to more personalized and effective healthy weight strategies.
* Analyses of average weight controlled for age, exercise frequency, fast food intake, and ancestry substructure.

Nick Furlotte

The Genetics of Bellies and Burgers

<img decoding="async" class="alignright size-full wp-image-219" title="feetscale" src="https://blog-api.23andme.com/wp-content/uploads/2008/05/feetscale.jpg" alt="" width="315" srcset="https://blogcms.23andme.com/wp-content/uploads/2008/05/feetscale.jpg 425w, https://blogcms.23andme.com/wp-content/uploads/2008/05/feetscale-300x199.jpg 300w" sizes="(max-width: 425px) 100vw, 425px" />
In 2009, 27% of Americans met the clinical criteria for obesity–a body mass index (BMI) of 30 or greater–7 percentage points higher than a mere 9 years earlier. Even this staggering 27% estimate may be too low. A large National Health and Nutrition Examination Study (NHANES) study estimated the prevalence of obesity at 34%. No wonder losing weight is a national preoccupation.
But how much control do we really exert over our weight? We all know people who seemingly gorge themselves at every meal but never gain an ounce and others who all too easily pack on the pounds.
In a paper published in <a href="http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000332" target="_blank" rel="noopener noreferrer">PLoS Medicine</a>, Shengxu Li and colleagues tackled a piece of that puzzle. Using a sample of 20,000 Europeans, they compared the predictive power of 12 SNPs known to influence BMI in sedentary and physically active individuals. While carrying a greater number of risky versions of these SNPs was associated with higher BMI in both groups, the association was much weaker in the physically active.
In the sedentary group, each additional risky variant translated to a 0.21 increase in BMI, or an extra 1.3 lbs (592 g) for someone 5&#8217;7 (170 cm). By comparison, in the physically active people, each additional risky variant  translated to a 0.13 increase in BMI, or an extra 0.8 lbs (397 g) for someone 5&#8217;7 (170 cm). Leading a physically active lifestyle, they concluded, was associated with a 40% reduction in the genetic predisposition to obesity.
Although we only have 9 of the 12 SNPs covered in our database, a quick analysis using our customers&#8217; data replicated their findings. Carrying more risky variants was predictive of a higher BMI overall, but this effect was much more pronounced among our customers who reported low levels of physical activity.
Of course, the 12 SNPs under investigation do not represent the totality of genetic predisposition to obesity. In fact, the 12 SNPs combined accounted for only 1.2% of the variation in weight among the sedentary individuals, and even less, 0.6%, among the physically active. Other genetic factors not measured in this research, such as rare variants associated with BMI, likely play a role as well.

Jeans Too Tight? Don’t Just Blame Your Genes.

<img decoding="async" class="right alignright" src="https://blog-api.23andme.com/wp-content/uploads/2008/05/feetscale.jpg" alt="feetscale.jpg" />The Atkins diet, the South Beach diet, the Grapefruit diet, the Cabbage Soup diet — we know all these fad diets have their limits, because ultimately, the only way to lose weight is to eat fewer calories and burn more.
But have you ever thought about what controls your appetite? What if your body didn’t tell you to stop eating when you’d consumed enough calories?
You&#8217;d gain weight, that&#8217;s what. It&#8217;s long been known that mutations in a gene called MC4R cause mice to become bigger and fatter than their regular counterparts.
It&#8217;s thought that eating a lot causes the body to turn on MC4R, which in turn tells the mice to stop eating by making them feel full. There are also rare variations that disrupt the human MC4R protein and cause children to eat too much, leading to severe childhood obesity.
Interesting, you say, but does this apply to the general population too? Research published online Sunday in the journal <a href="https://www.nature.com/ng/index.html" target="_blank" rel="noopener noreferrer">Nature Genetics</a> suggests that the answer is yes.

A large study of over 77,000 Europeans by <a href="https://www.nature.com/ng/journal/vaop/ncurrent/abs/ng.140.html" target="_blank" rel="noopener noreferrer">Loos et al.</a> found a SNP near the MC4R gene, rs17782313, that was strongly associated with body mass index (BMI), a measure of obesity. (To calculate your own BMI, go to: http://www.nhlbisupport.com/bmi/bmicalc.htm) They found that each copy of the C version of rs17782313 was associated with an increase of 0.22 BMI units in adults (for a person of my height, 5 ft 3 in, that’s a little over a pound). In children, they found that this SNP had an even larger effect. Unlike the rare changes in MC4R that cause severe childhood obesity, 30 to 50% of the population has at least one copy of the C allele of rs17782313.
A second paper by <a href="https://www.nature.com/ng/journal/vaop/ncurrent/abs/ng.156.html" target="_blank" rel="noopener noreferrer">Chambers et al.</a>, also published online Sunday in Nature Genetics, studied more than 14,000 Indian Asians and Europeans and found that a different SNP near MC4R, rs12970134, is associated with waist circumference. Each copy of the A version is associated with a 0.88 cm (0.3 in) increase in waist circumference. That means that on average, the waists of people with two copies of the A version of rs12970134 are 0.6 inches larger than the waists of people with two copies of the other version of the SNP. Talk about pinching an inch!
Fortunately for most of us, genes are only one player in our risk for obesity, as our behavior and environment can still play a large role in maintaining a healthy weight.
Calculating your BMI: You can calculate your own BMI using the following formula: multiply your weight in pounds by 0.454 to get your weight in kilograms. Then multiply your height in inches by .0254 to get your height in meters and square the result. Divide your weight in kilograms by your height in meters squared to get your BMI. A BMI less than 18.5 is considered underweight, between 18.5 and 24.9 normal, between 25 and 29.9 overweight, and above 30, obese.

Weight — Page 2

Tipping the scales: Participants make healthy dietary changes in response to direct-to-consumer genetic test results

23andMe Launches Landmark Weight Loss Study

The Genetics of Bellies and Burgers

Jeans Too Tight? Don’t Just Blame Your Genes.

MC4R Gene Associated with Body Mass

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