Friday, April 18, 2014

Who Wants To Snack Forever? He Must Be an Idiot, 'cause Snacking is Bad for You - Expect It's Protein and Doesn't Increase Your Energy Intake Way Beyond Your Demands

Hands off, if you want to stay lean!
I guess there is a bit of a hyperbole involved in the headline of today's SuppVersity article. In view of the latest results of an experiment that was conducted by scientists from the San Diego State University, it's yet probably not totally beside the point.

Zachary Clayton and his colleagues did after all find that their subjects showed similar unwanted metabolic alterations when they consumed two 100kcal snacks per day for 8 weeks (Clayton. 2014).
You can learn more about snacking & co at the SuppVersity

Fridge Raiders? Night Time Snacking

Protein Snack Shifts Macro Ratio for the Better

High Meal Frequency, High Body Fat

Alternate Fasting: Eating only a snack

The Optimal Protein Blend For Every Purpose

High or Low Protein? Casein or Whey?
In that, it did not make a difference if the snack was "healthy" (dried plums) or unhealthy (a highly refined low-fat muffin). Both snacks had negative effects on the amount of high molecular weight adiponectin - in all fairness, it must be said, though, that the decrease in the muffin group was almost 2x higher than it was in the plum group.
Figure 1: Contribution of snacking to total daily energy intake by year and age (left; Jahns. 1996); prevalence of overweight among US children and adolescents (right; CDC data)
In this context, it's particularly interesting to take a look at the parallelism between the increase in snacking in 6-11 year-olds (+4% of total energy intake) and the corresponding 4% increase in childhood obesity rates in from the early to the late 1990s (see Figure 1).
Protein has a long(er) lasting postprandial thermogenic effect than carbs (LeBlanc. 1991)
Why is protein the exception? There are actually several reasons. Firstly, it's satiating (see Figure 2), secondly, it's anabolic (see previous articles on protein), thirdly, it's themogenic (Johnston. 2002) and fourthly, it's stored as body fat only comparatively inefectively (see Bray study). Obviously, this does not mean that you can add three 50g protein shakes and thus 600kcal to a 2,000kcal baseline without paying a fat price for your gluttony.
What it does mean, though, is that you are probably about to become leaner and more muscular if you add the same three protein shakes to a 3,000kcal baseline and throw out the Twinkies, Dingdongs and the last slice of pizza to "compensate" for the additional energy intake.
Could this actually be a result of reductions in high molecular weight adiponectin? If we consider the fact that HMW adiponectin...
  • This does not apply to I diabetes: It's not yet sure why, but the contemporary evidence suggests that, unlike type II,  type I diabetes is often characterized by abnormally high levels of high molecular weight adiponectin (Galler. 2007; Leth. 2008). For someone with diabetes anti-bodies, the correlations mentioned to the left of this box are thus meaningless.
    or rather reduced levels of it are associated with increased risk of type II diabetes (Nakashima. 2006; Heidemann. 2008)
  • correlates better with blood glucose management than total adiponectin (Trujillo. 2005) and can be used to predict insulin resistance and metabolic syndrome (Hara. 2006)
  • predicts the outcome in patients with coronary artery disease and is independently associated with the extent of coronary artery disease in men (Inoue. 2007; von Eynatten. 2008)
  • activates AMPK and suppresses cytokine-induced NF-κB activation in vascular endothelial cells and will thus support the self-repair of your cardiovascular system (Hattori. 2008)
  • is supposed to be particularly active as a "weight loss trigger" in the brain (Qi. 2004)
  • rises in response to the administration to certain hypolipidemic and hypoglycemic drugs (Oki. 2007)
Moreover, previous studies have already established a link between higher circulating total and high-molecular-weight adiponectin and a "healthy" diet (Fargnoli. 2008). The fact that the official "healthy diet prescription" which was also at the heart of the corresponing s analysis of the effects of a "healthy diet" on HMW adiponectin advocates the use of dried plums as snacks, is thus kind of funny. With the latest data from the San Diego State University we do after all have (albeit only borderline significant) evidence that plums and snacking in general "may not be advantageous in promoting anthropometric or metabolic alterations in overweight individuals." (Clayton. 2014)
Not advantageous? Can this be? At least for the group of overweight individuals, Clayton et al. are referencing in the previously cited conclusion to their study, snacking certainly isn't healthy.

Figure 2: Satiety effect of high protein (77% of energy from protein), high fat  (58% of energy from fat), and high carb (84% of energy from carbs) snacks measured as the latency of the spontaneous request for dinner, when the snack was consumed 240min after a standardized lunch had been served (Marmonier. 2000)
It's important to note, though, that this is in contrast to normal-weight individuals who have been snacking "naturally" for their whole lives. Accordingly, Larson et al. observed in their latest review of the literature that the contemporary evidence would suggest that there is either "no relationship between snacking behavior and weight status in youths" or"that young people who consumed more snacks were less likely to be obese" (Larson. 2013).

As an experiment by scientists from the Shahid Beheshti University of Medical Sciences clearly indicates, this is obviously not the case for the consumption of energy dense snacks (Mirmiran. 2013) - exactly those food items that are responsible for the ever increasing contribution of snacks to the average American's overall energy intake. No wonder that Westenhoefer et al. were able to show that a reduced snack frequency is one of the various determinants of successful weight loss and, more importantly, weight maintenance (Westenhoefer. 2004)
  • Bray, George A., et al. "Effect of dietary protein content on weight gain, energy expenditure, and body composition during overeating: a randomized controlled trial." JAMA 307.1 (2012): 47-55.
  • Fargnoli, Jessica L., et al. "Adherence to healthy eating patterns is associated with higher circulating total and high-molecular-weight adiponectin and lower resistin concentrations in women from the Nurses' Health Study." The American journal of clinical nutrition 88.5 (2008): 1213-1224.
  • Galler, Angela, et al. "Elevated serum levels of adiponectin in children, adolescents and young adults with type 1 diabetes and the impact of age, gender, body mass index and metabolic control: a longitudinal study." European Journal of Endocrinology 157.4 (2007): 481-489.
  • Hara, Kazuo, et al. "Measurement of the high–molecular weight form of adiponectin in plasma is useful for the prediction of insulin resistance and metabolic syndrome." Diabetes care 29.6 (2006): 1357-1362.
  • Hattori, Yoshiyuki, et al. "High molecular weight adiponectin activates AMPK and suppresses cytokine-induced NF-κB activation in vascular endothelial cells." FEBS letters 582.12 (2008): 1719-1724.
  • Heidemann, Christin, et al. "Total and high-molecular-weight adiponectin and resistin in relation to the risk for type 2 diabetes in women." Annals of internal medicine 149.5 (2008): 307-316.
  • Inoue, Teruo, et al. "High molecular weight adiponectin as a predictor of long-term clinical outcome in patients with coronary artery disease." The American journal of cardiology 100.4 (2007): 569-574.
  • Larson, Nicole, and Mary Story. "A review of snacking patterns among children and adolescents: what are the implications of snacking for weight status?." Childhood Obesity 9.2 (2013): 104-115. 
  • LeBlanc, J., P. Diamond, and A. Nadeau. "Thermogenic and hormonal responses to palatable protein and carbohydrate rich food." Hormone and metabolic research 23.07 (1991): 336-340.
  • Leth, Henrik, et al. "Elevated levels of high-molecular-weight adiponectin in type 1 diabetes." Journal of Clinical Endocrinology & Metabolism 93.8 (2008): 3186-3191.
  • Marmonier, C., D. Chapelot, and J. Louis-Sylvestre. "Effects of macronutrient content and energy density of snacks consumed in a satiety state on the onset of the next meal." Appetite 34.2 (2000): 161-168.
  • Nakashima, Reiko, et al. "Decreased total and high molecular weight adiponectin are independent risk factors for the development of type 2 diabetes in Japanese-Americans." Journal of Clinical Endocrinology & Metabolism 91.10 (2006): 3873-3877. 
  • Oki, Kenji, et al. "Fenofibrate increases high molecular weight adiponectin in subjects with hypertriglyceridemia." Endocrine journal 54.3 (2007): 431-435.
  • Qi, Yong, et al. "Adiponectin acts in the brain to decrease body weight." Nature medicine 10.5 (2004): 524-529.
  • Trujillo, M. E., et al. "Serum high molecular weight complex of adiponectin correlates better with glucose tolerance than total serum adiponectin in Indo-Asian males." Diabetologia 48.6 (2005): 1084-1087.
  • Tsutamoto, Takayoshi, et al. "Total and high molecular weight adiponectin, haemodynamics, and mortality in patients with chronic heart failure." European heart journal 28.14 (2007): 1723-1730.
  • von Eynatten, Maximilian, et al. "High-molecular weight adiponectin is independently associated with the extent of coronary artery disease in men." Atherosclerosis 199.1 (2008): 123-128.
  • Westenhoefer, J., et al. "Behavioural correlates of successful weight reduction over 3 y. Results from the Lean Habits Study." International journal of obesity 28.2 (2004): 334-335.