TLDR;
This video explains biological value, the science behind whey protein, its types, benefits, and precautions. It covers the composition of whey protein, how it aids muscle development through the mTOR pathway, and its broader health benefits beyond muscle building. The video also discusses potential risks and who should exercise caution when consuming whey protein.
- Biological Value (BV) measures the amount of protein retained in the body.
- Whey protein has the highest BV, making it effective for muscle development.
- Whey protein contains essential components like lactoglobulin, lactalbumin, and immunoglobulins.
- It activates the mTOR pathway, which enhances protein synthesis in muscle cells.
- Whey protein offers antioxidant benefits through glutathione production but may pose risks for individuals with kidney issues, lactose intolerance, or a family history of diabetes.
Introduction to Biological Value and Protein [0:00]
The video starts by defining biological value (BV) as the measure of protein retained by the body, emphasizing its importance in understanding protein and whey protein. The formula for BV is Nitrogen Retained (NR) divided by Nitrogen Absorbed (NA), multiplied by 100. Muscles are made of protein, which in turn is composed of amino acids, which are composed of nitrogen. Biological value indicates how much of the absorbed protein is available to the muscles. Whey protein has the highest biological value, even higher than eggs, meaning it is the most effective form of protein for muscle retention.
Why Whey Protein? Understanding Its Science [1:52]
The video addresses why whey protein is preferred, explaining that it has the highest biological value among proteins. When you consume 100 grams of protein, not all of it is absorbed; some is excreted. The portion that is absorbed isn't fully utilized by the muscles. Biological value is calculated by dividing the protein that muscles receive by the protein absorbed. Whey protein is not a single molecule but a mix of globular proteins, a heterogeneous mixture found naturally in milk. Cow's milk is considered the best source of whey protein.
Whey Protein Composition and Production [3:58]
Whey protein is produced by separating it from milk. Milk contains two types of proteins: casein (80%) and whey (20%). To isolate whey, milk is curdled, separating the casein, which coagulates and settles. The remaining liquid is whey protein. While you can make whey protein at home, the yield is very small because whey constitutes a small fraction of the total protein in milk. Whey protein is composed of three components: lactoglobulin, lactalbumin, and immunoglobulins.
Key Components of Whey Protein: Lactoglobulin, Lactalbumin, and Immunoglobulins [6:29]
The components of whey protein are detailed, starting with lactoglobulin, which makes up about 55% of whey protein. Lactoglobulin is related to retinol (Vitamin A) and can cause allergies in some individuals. It includes beta-lactoglobulin. The second component, lactalbumin (alpha-lactalbumin), accounts for 20-30% of whey protein. The third component is immunoglobulins (IgG and IgA), which support the immune system. Additionally, whey protein contains vitamins A, E, D, and B12, along with lactoferrin, which binds to iron and helps kill bacteria, thus boosting immunity.
Digestion and Absorption of Whey Protein [9:44]
The video explains where and how whey protein is digested. When food is consumed, it goes into the stomach, then the intestine. Whey protein is known as a "fast protein" because it is quickly digested. Unlike casein, which forms micelles in the stomach and digests slowly, whey protein is not significantly affected by stomach acid (HCL). It passes directly into the intestine, where proteases break it down, allowing it to be rapidly absorbed into the bloodstream. Studies show that amino acid levels in the blood spike within 10-15 minutes after whey protein consumption.
How Whey Protein Builds Muscle: The mTOR Pathway [13:08]
The mechanism by which whey protein builds muscle involves the mTOR (mammalian target of rapamycin) pathway. Whey protein contains branched-chain amino acids (BCAAs), particularly leucine. Leucine is crucial because it easily enters muscle cells. Muscle cells have a membrane with gates that open readily for leucine. Once inside the muscle cell, leucine activates the mTOR pathway, which in turn stimulates DNA to promote protein synthesis.
Activating Protein Synthesis: Ribosomes and Translation [18:35]
Once activated, mTOR stimulates two key molecules within the muscle cells: P70S6K and 4E-BP1. P70S6K activates ribosomes, the protein factories of the cell, while 4E-BP1 enhances translation, the process by which amino acids combine to form proteins. This process increases protein production in muscles by approximately 200 times. With an increased rate of protein synthesis and available amino acids, new muscle fibers are formed, leading to muscle thickening and increased muscle mass.
Types of Whey Protein: Concentrate, Isolate, and Hydrolysate [22:57]
The video discusses the three main types of whey protein available on the market: concentrate, isolate, and hydrolysate. Whey concentrate contains 30-80% protein, along with lactose and fat. Whey isolate is more refined, with approximately 90% protein and reduced lactose and fat. Whey hydrolysate is pre-digested with protein enzymes, resulting in peptides that are absorbed directly into the body without digestion, leading to an insulin spike.
Beyond Muscles: Additional Benefits of Whey Protein [27:34]
Whey protein is not only for muscle building but also boosts the antioxidant glutathione, which helps eliminate harmful elements in the body. Whey protein provides cysteine, an amino acid that aids in glutathione production. This makes whey protein beneficial for individuals beyond gym-goers, including those with HIV/AIDS, immunocompromised patients, and cancer patients, provided they are not lactose intolerant.
Precautions and Considerations for Whey Protein Consumption [28:51]
The video outlines precautions for whey protein consumption. Since protein converts to urea, excessive intake can strain the kidneys. Individuals with a family history of chronic kidney disease or high blood pressure should consult a doctor before taking whey protein. Those with lactose intolerance should opt for whey isolate. Additionally, whey protein, especially in isolated or hydrolyzed forms, can cause insulin spikes, so individuals with a family history of diabetes should use it cautiously.
Conclusion: Who Can Take Whey Protein and How Much? [30:41]
In conclusion, whey protein can be taken if there are no issues with lactose intolerance, kidney problems, high blood pressure, or diabetes. Women can also take whey protein, as it is equally beneficial for them. The amount of whey protein to take depends on muscle mass and fitness goals. For a healthy lifestyle, sufficient protein can be obtained from a balanced diet, and it is recommended to consult a qualified dietitian for personalized dietary advice. Pregnant women and others with specific health conditions should consult their doctors before using whey protein.
