The World Health Organization (WHO) has labelled human obesity a world-wide epidemic (Giskes, van, Avendano-Pabon, & Brug, 2011; Pimentel, Arimura, de Moura, Silva, & de Sousa, 2010). In the last couple of decades, America alone has seen prevalence rates of obesity almost double from 12.8% to 22.5% (Kuczmarski, Flegal, Campbell, & Johnson, 1994; Mokdad et al., 1999).
It is now common knowledge that reduction of body weight to counter obesity helps fight its ill-effects as well – diabetes and cardiovascular-metabolic diseases. Interventions to reduce body weight, in the present scenario, have thus assumed great importance. Exercise alone, however, has been unsuccessful in controlling the rampant spread of obesity epidemic. A combination of exercise and dietary interventions seems to be a better option.
Supplementation with milk serum proteins, especially, whey protein has emerged as a new and exciting nutritional method. Overwhelming evidence supports the view that whey protein not only plays a role in increasing resting energy expenditure (Luhovyy, Akhavan, & Anderson, 2007), loss of body fat and growth (and maintenance) of lean mass but also reduces risks associated with obesity and cardiovascular-metabolic diseases. So much so that most researchers feel whey protein supplementation should now be a routine part of management and treatment protocols for almost all cases of obesity, diabetes and cardiovascular-metabolic conditions.
What Is Whey Protein?
Whey protein is one of the two major proteins of milk – the other being casein. Being high in its BCAA content (branched-chain amino acids – leucine, isoleucine and valine) – whey plays an important role in growth and repair of tissues – especially muscles (Bowen, Noakes, & Clifton, 2006).
Additionally milk serum proteins – proteins that remain soluble in milk serum, for instance β-lactoglobulins, α-lactalbumin, immunoglobulins, lactoferrins and others (Hulmi, Lockwood, & Stout, 2010; Luhovyy et al., 2007) – afford a number of other benefits, viz. improved protein synthesis, better absorption of mineral, reduced blood sugar, reduced blood lipids and improved insulin sensitivity (Pal, Ellis, & Ho, 2010; Lan-Pidhainy & Wolever, 2010; Pilvi, Korpela, Huttunen, Vapaatalo, & Mervaala, 2007).
Role of Whey Protein in prevention of Obesity and Cardiovascular-Metabolic Conditions
Let us have a brief look at how whey protein exerts its beneficial effects.
- Greater reduction of body fat compared to other proteins or other dietary ingredients (Takahashi, de Oliveira, Moreto, Portero-McLellan, & Burini, 2010; Frestedt, Zenk, Kuskowski, Ward, & Bastian, 2008; Baer et al., 2011; Pilvi et al., 2008; Mortensen et al., 2009)
- Growth and maintenance of lean mass – high levels of leucine (present in whey) allows for excess calories to be used for muscle growth rather than being stored as fat (Pilvi et al., 2007)
- Increased hormone sensitivity including that for leptin (Pilvi et al., 2008) and insulin (Pal & Ellis, 2010)
- Better glycemic control (blood sugar level control) with improved insulin sensitivity and increased fasting and postprandial (post-food) insulin release (Pal & Ellis, 2010; Frid, Nilsson, Holst, & Bjorck, 2005; Li et al., 2010; Mortensen et al., 2012). Although insulin levels are increased, this doesn’t translate into fat deposition (one of the actions of insulin) – the high leucine content of whey prevents fat deposition from occurring (Pal & Ellis, 2010).
- Reduced risk of cardiovascular disease by decreasing blood triacylglycerol (fat) levels (Pal et al., 2010; Pal & Ellis, 2010; Pal & Ellis, 2010; Mortensen et al., 2009)
- Whey protein amino acids like α-lactalbumin and β-lactglobulin act as precursors of molecules which inhibit ACE (angiotensin-converting enzyme). Thus, whey protein indirectly plays a role in countering elevated blood pressure (Pal & Ellis, 2010; Pal & Ellis, 2010; Takahashi et al., 2011).
In addition to the above effects, whey has some other amazing benefits like liver protection, anti-inflammatory and anti-oxidative stress action.
Although whey protein supplementation is already popular amongst the athletic population, it has the potential to be part of almost all prescriptions for those suffering from metabolic diseases, not to mention the ones looking to shed excess weight.
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Bowen, J., Noakes, M., & Clifton, P. M. (2006). Appetite regulatory hormone responses to various dietary proteins differ by body mass index status despite similar reductions in ad libitum energy intake. J Clin Endocrinol.Metab, 91, 2913-2919.
Frestedt, J. L., Zenk, J. L., Kuskowski, M. A., Ward, L. S., & Bastian, E. D. (2008). A whey-protein supplement increases fat loss and spares lean muscle in obese subjects: a randomized human clinical study. Nutr.Metab (Lond), 5, 8.
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