Scitec Nutrition Wall of Protein at FIBO 2013

A protein supplement is a

dietary supplement A dietary supplement is a manufactured product intended to supplement a person's diet by taking a pill (pharmacy), pill, capsule (pharmacy), capsule, tablet (pharmacy), tablet, powder, or liquid. A supplement can provide nutrients eithe ...

or a

bodybuilding supplement Bodybuilding supplements are dietary supplements commonly used by those involved in bodybuilding, weightlifting, mixed martial arts, and athletics for the purpose of facilitating an increase in lean body mass. Bodybuilding supplements may contai ...

, and usually comes in the form of a

protein bar Protein bars are convenience food that contain a high proportion of protein relative to carbohydrates and fats. Despite the label focusing on protein, many mass-marketed protein bars contain more added sugar than some desserts like cookies or ...

, protein powder, and even readily available as a protein shake. Protein supplements are usually made from whey, plant, and/or meat sources. Protein supplements are extracts or concentrates of high protein foodstuffs, used in bodybuilding and as dietary supplements to fulfill protein intake in a lean and pure source of proteins and

amino acids Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although over 500 amino acids exist in nature, by far the most important are the Proteinogenic amino acid, 22 α-amino acids incorporated into p ...

. They have three main variants: concentrate (food is taken and concentrated into a smaller volume with some fat and carb present), isolate (proteins and amino acids are completely isolated, mostly leaving proteins and amino acids), and hydrolyze (a protein supplement is exposed to enzymes and partially digested). Some protein supplements contain digestive enzymes as an additive for digestion and absorption. The range of grams of protein per scoop varies from brand to brand, some of the more high end protein powders reaching 30g of protein per scoop.

Effects

Metabolism

A meta-study found that in the first few weeks of strength training with untrained individuals, changes in

lean body mass Lean body mass (LBM), sometimes conflated with , is a component of body composition. Fat-free mass (FFM) is calculated by subtracting body fat weight from total body weight: total body weight is lean plus fat. In equations: :LBM = BW ...

and

muscle strength Skeletal muscle (commonly referred to as muscle) is one of the three types of vertebrate muscle tissue, the others being cardiac muscle and smooth muscle. They are part of the somatic nervous system, voluntary muscular system and typically are a ...

during the initial weeks of

strength training Strength training, also known as weight training or resistance training, is exercise designed to improve physical strength. It is often associated with the lifting of Weightlifting, weights. It can also incorporate techniques such as bodyweigh ...

are not influenced by the protein supplementation, but after the first few weeks, protein supplementation “may promote muscle hypertrophy and enhance gains in muscle strength in both untrained and trained individuals” Also, whey-protein supplementation in

overweight Being overweight is having more body fat than is optimally healthy. Being overweight is especially common where food supplies are plentiful and lifestyles are sedentary. , excess weight reached epidemic proportions globally, with more than ...

individuals may reduce the

body weight Human body weight is a person's mass or weight. Strictly speaking, body weight is the measurement of mass without items located on the person. Practically though, body weight may be measured with clothes on, but without shoes or heavy accessori ...

, total

fat mass Adipose tissue (also known as body fat or simply fat) is a loose connective tissue composed mostly of adipocytes. It also contains the stromal vascular fraction (SVF) of cells including preadipocytes, fibroblasts, vascular endothelial cells and ...

and risk factors for

cardiovascular disease Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina, heart attack), heart failure, hypertensive heart disease, rheumati ...

s. When combined with

, protein supplementation promotes greater gains in lean body mass and muscle strength as the intensity, frequency, and duration of strength training increases. It increases the muscles' strength and

size Size in general is the Magnitude (mathematics), magnitude or dimensions of a thing. More specifically, ''geometrical size'' (or ''spatial size'') can refer to three geometrical measures: length, area, or volume. Length can be generalized ...

, during prolonged strength training in healthy adults. A meta-study concluded that intake of protein supplements higher than around 1.6 g/kg/day do not further improve the gains in FFM (fat free mass) “at least for younger individuals”, with a confidence interval from 1.03 to 2.20 so “it may be prudent to recommend ~2.2 g protein/kg/d for those seeking to maximize resistance training-induced gains in FFM”.

Protein and aging

As people get older, aging reduces the effect of protein intake, and experts in the field of protein and aging recommend a protein intake between 1.2 and 2.0 g/kg/day or higher for elderly adults. Higher-than-ADA protein recommendations are especially important if they have acute or chronic diseases. Increased

resistance training Strength training, also known as weight training or resistance training, is exercise designed to improve physical strength. It is often associated with the lifting of weights. It can also incorporate techniques such as bodyweight exercises (e ...

also helps balance aging's negative effect on muscle mass. A study group concluded: "Older people with severe kidney disease (i.e., estimated

GFR GFR may refer to: * Gas-cooled fast reactor * Gefreiter * General fertility rate * Glomerular filtration rate * Government Flight Representative * Grand Forks Railway, a Canadian railway * Grand Funk Railroad, an American rock band * Grup Ferovi ...

less than 30 mL/min/1.73m²), but who are not on dialysis, are an exception to this rule; these individuals may need to limit protein intake."

Timing

Past studies propose that spreading protein intake through the day (with a maximum of 30g at a time) achieves maximal total stimulation of muscle protein synthesis. However, recent studies suggest that protein intake for muscle gain can be taken either throughout the day or at one time, if that is more convenient. There is no evidence supporting specific pre/post-workout timing for protein-supplement intakes, despite the widely held belief that pre- or post-workout protein supplementation would be more effective.

Chronic kidney disease

Nutritional status can be altered in people living with chronic kidney disease (CKD). There is moderate-certainty evidence that regular consumption of oral protein-based nutritional supplements may increase serum

albumin Albumin is a family of globular proteins, the most common of which are the serum albumins. All of the proteins of the albumin family are water- soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Alb ...

, a protein that can be lower in people with CKD, due to increased loss in urine and malnutrition. Improvements in albumin following protein supplementation may be greater in those who require hemodialysis or who are malnourished. Pre-albumin levels and mid-arm circumference measurements may also be increased following supplementation, though the certainty of evidence is low. Although these indicate possible improvements in nutritional status, it is unclear whether protein supplements affect quality of life, life expectancy, inflammation or body composition.

References