|
|
|
|
I hope this newsletter finds you and your family well. We are officially into the holiday season and I would like to take this opportunity to wish you and your families all the blessing and happiness of the season. I hope all of you are to spend time with your loved ones.
Diet. Nobody really wants to think about it right now with that leftover pumpkin pie in the refrigerator, but carbs are something I get asked about all the time. Low carb, keto, Atkins, Paleo, the list goes on. Do these diets work? The first study looked at people who had lost weight and then went on one of three levels of carb diets. Read on for the findings!
Should we spend the extra money on organic foods? Is it worth it? The second study looks at organic food intake and rates of cancer. This might change your mind about organics.
FOMO, the fear of missing out is ubiquitous in our society, especially in younger people. Social media has exacerbated this in our population. But does social medial make us more depressed or anxious? Should we limit our use? The third article explores these questions.
Click on the links the the left to check out our
web site
.
|
|
Do Carbs Matter?
|
Effects of low carbohydrate diet on energy expenditure
How does the make up of your diet, specifically carbohydrate intake affect your metabolic rate? That is the question researchers in this multicenter study of 164 overweight adults sought to answer. The participants lost an average of 12% of
their body weight and were then were randomly assigned to either a 60% carbohydrate diet, 40% carbohydrate diet or 20% carbohydrate diet for 20 weeks. Energy expenditure and levels of the hormones leptin and ghrelin were measured. Ghrelin is often called the hunger hormone because it stimulates appetite, increases food intake and promotes fat storage. Leptin is an appetite suppressant. Many overweight people have built up resistance to the effects of leptin. Lowering carbohydrate intake increased energy expenditure by 52 kcal/d for every 10% decrease in carbohydrate intake resulting in over 200 kcal/day difference between the higher carb group and the low carb group. This difference was even more profound in the people who were the highest insulin secreters baseline (up to 478 kcal/d). Ghrelin was significantly lower in the low carb group.
Abstract:
- Objective To determine the effects of diets varying in carbohydrate to fat ratio on total energy expenditure.
- Setting Multicenter collaboration at US two sites, August 2014 to May 2017.
- Participants 164 adults aged 18-65 years with a body mass index of 25 or more.
- Interventions After 12% (within 2%) weight loss on a run-in diet, participants were randomly assigned to one of three test diets according to carbohydrate content (high, 60%, n=54; moderate, 40%, n=53; or low, 20%, n=57) for 20 weeks. Test diets were controlled for protein and were energy adjusted to maintain weight loss within 2 kg. To test for effect modification predicted by the carbohydrate-insulin model, the sample was divided into thirds of pre-weight loss insulin secretion (insulin concentration 30 minutes after oral glucose).
- Main outcome measures The primary outcome was total energy expenditure, measured with doubly labeled water, by intention-to-treat analysis. Per protocol analysis included participants who maintained target weight loss, potentially providing a more precise effect estimate. Secondary outcomes were resting energy expenditure, measures of physical activity, and levels of the metabolic hormones leptin and ghrelin.
- Results Total energy expenditure differed by diet in the intention-to-treat analysis (n=162, P=0.002), with a linear trend of 52 kcal/d (95% confidence interval 23 to 82) for every 10% decrease in the contribution of carbohydrate to total energy intake (1 kcal=4.18 kJ=0.00418 MJ). Change in total energy expenditure was 91 kcal/d (95% confidence interval −29 to 210) greater in participants assigned to the moderate carbohydrate diet and 209 kcal/d (91 to 326) greater in those assigned to the low carbohydrate diet compared with the high carbohydrate diet. In the per protocol analysis (n=120, P<0.001), the respective differences were 131 kcal/d (−6 to 267) and 278 kcal/d (144 to 411). Among participants in the highest third of pre-weight loss insulin secretion, the difference between the low and high carbohydrate diet was 308 kcal/d in the intention-to-treat analysis and 478 kcal/d in the per protocol analysis (P<0.004). Ghrelin was significantly lower in participants assigned to the low carbohydrate diet compared with those assigned to the high carbohydrate diet (both analyses). Leptin was also significantly lower in participants assigned to the low carbohydrate diet (per protocol).
- Conclusions Consistent with the carbohydrate-insulin model, lowering dietary carbohydrate increased energy expenditure during weight loss maintenance. This metabolic effect may improve the success of obesity treatment, especially among those with high insulin secretion.
High carb, low carb, moderate carb, what's the best diet for weight control? This study tries to answer the question. A group of overweight people lost an average of 12% of their body weight and were then placed into either a higher carb, moderate carb or low carb diet group. The people in the low carb group burned significantly more calories during the day independent of activity. Their hunger hormone ghrelin was lower too. It is interesting the most insulin resistant group found the low carb diet to be most effective. The message here seems to be that lower carb diets increase metabolic rate, decrease hunger hormones, and are likely especially effective for the most insulin resistant people (diabetics or prediabetics). Even the 20% carb diet isn't nearly as low as many "low carb" diets such as Atkins or Keto. It looks like getting carbs ultra low may not be necessary to get our bodies to the point of raising metabolic rate, lowering hunger hormones and improving insulin resistance. Even a moderate decrease in carbs is beneficial from the typical diet which is often around 60% carbs or more.
|
|
|
Organic foods for cancer prevention
There are over 85,000 chemicals produced by man. Less than 1% have been studied for safety. Multiple pesticides have human carcinogenic potential. Reports of pesticides in drinking water are becoming more frequent. How does this affect our food? This study, from JAMA Internal Medicine studied almost 69,000 people about their organic food consumption and followed them for over 7 years to evaluate for the development of cancer. In the group there were 1340 cancer cases with the most common being breast, prostate, skin, colorectal, and lymphomas. The subjects with the higher reported intake of organic foods had reduced rates of cancer.
Abstract:
- Objective To prospectively investigate the association between organic food consumption and the risk of cancer in a large cohort of French adults.
- Design, Setting, and Participants In this population-based prospective cohort study among French adult volunteers, data were included from participants with available information on organic food consumption frequency and dietary intake. For 16 products, participants reported their consumption frequency of labeled organic foods (never, occasionally, or most of the time). An organic food score was then computed (range, 0-32 points). The follow-up dates were May 10, 2009, to November 30, 2016.
- Main Outcomes and Measures This study estimated the risk of cancer in association with the organic food score (modeled as quartiles) using Cox proportional hazards regression models adjusted for potential cancer risk factors.
- Results Among 68,946 participants (78.0% female; mean [SD] age at baseline, 44.2 [14.5] years), 1340 first incident cancer cases were identified during follow-up, with the most prevalent being 459 breast cancers, 180 prostate cancers, 135 skin cancers, 99 colorectal cancers, 47 non-Hodgkin lymphomas, and 15 other lymphomas. High organic food scores were inversely associated with the overall risk of cancer (hazard ratio for quartile 4 vs quartile 1, 0.75; 95% CI, 0.63-0.88; P for trend = .001; absolute risk reduction, 0.6%; hazard ratio for a 5-point increase, 0.92; 95% CI, 0.88-0.96)
- Conclusions and Relevance A higher frequency of organic food consumption was associated with a reduced risk of cancer. Although the study findings need to be confirmed, promoting organic food consumption in the general population could be a promising preventive strategy against cancer.
I'm often asked if organic foods are worth the extra cost. This study adds to the information we have regarding organic food intake and cancers. It appears from this study that those who eat organic have lower rates of cancer. This is hard to quantify perfectly as only 2% of subjects developed cancer. The sample was also 78% women which could skew the results and certainly explains the high rate of breast cancer as compared to other cancers. People who volunteer for studies tend to be healthier and people who eat organic probably have more healthy habits in other areas outside of nutrition which could explain some of the findings. However, the findings are still compelling.
I have generally recommended organic whenever possible and will continue to do so. It certainly can't hurt and it may be helpful. A good way to get organic fruits and vegetables at a reasonable price is to buy fresh frozen. This maintains the nutrients and are a good choice during winter when we can't get local fresh fruits and vegetables. During the summer, our local organic farmer's market may be worth the trip.
|
|
FOMO
|
Cutting time on social medial reduces risk of depression and loneliness.
Social media is a significant part of people's lives. Sixty-eight percent of adults in the United States have Facebook accounts and 75% use these accounts daily. In the 18-24 yo age group 78% use Snapchat and 71% use Instagram. Self reported Facebook and Instagram usage has been found to correlate with symptoms of depression and higher usage of Facebook is associated with lower self esteem and higher loneliness. This study reduced the time the subjects spent on each social media platform to 10 minutes each or 30 minutes total daily time. Seven validated scales of well-being were used to determine levels of social support, fear of missing out (FOMO), loneliness, anxiety, depression, self-esteem and self-acceptance were used. At the end of 3 weeks, the group which decreased their social media use had declines in loneliness and depression scores, especially for those who were higher on the scales (most depressive symptoms).
Abstract:
- Introduction: Given the breadth of correlational research linking social media use to worse well-being, we undertook an experimental study to investigate the potential causal role that social media plays in this relationship.
- Method: After a week of baseline monitoring, 143 undergraduates at the University of Pennsylvania were randomly assigned to either limit Facebook, Instagram and Snapchat use to 10 minutes, per platform, per day, or to use social media as usual for three weeks.
- Results: The limited use group showed significant reductions in loneliness and depression over three weeks compared to the control group. Both groups showed significant decreases in anxiety and fear of missing out over baseline, suggesting a benefit of increased self-monitoring.
- Discussion: Our findings strongly suggest that limiting social media use to approximately 30 minutes per day may lead to significant improvement in well-being.
I found it interesting that "social media" made people more depressed and lonely. It could be that people who are already depressed and lonely spend more time on social media than others but that wasn't necessarily seen in this particular study. FOMO (fear of missing out) motivates people to spend more time on social media. This study did have some weaknesses, it had a high attrition rate (college students) and it didn't monitor other significant social media sites such as Twitter, Pinterest, Tumblr, and dating apps. "
Not comparing my life to the lives of others had a much
stronger impact than I expected, and I felt a lot more positive
about myself during those weeks." Perhaps that is the take home message.
|
|
Thank you for taking the time to read through this newsletter. I hope you have found this information useful as we work together to optimize your health. Feel free to pass this on to anyone you think would benefit from this information.
You can find previous newsletters archived on my website here.
As always, if you have questions about anything in this newsletter or have topics you would like me to address, please feel free to contact me by
email
, phone, or just stop by!
To Your Good Health,
Mark Niedfeldt, M.D.
|
|
|
