What Are Peptides?
Peptides and proteins are both made up of amino acids that are linked together (by peptide bonds, hence the name) in long chains called polymers. The only thing that separates peptides from proteins is how big they are. While there is no absolute cutoff, peptides are made up of fewer amino acids than proteins and hence are much smaller. In general, any amino acid chain that is longer than fifty residues in length is referred to as a protein. This is because after growing beyond 50 amino acids, peptides start to fold back on themselves creating shapes and bonds that are referred to as secondary structure. Peptides are almost always linear, with minimal secondary structure (lariat loops are sometimes observed), hence the size cut off.
So, peptides are smaller, simpler versions of proteins. But saying that does not do justice to the role these biochemicals play in everyday life. Research shows that peptides are primarily signaling molecules used to alter the ebb and flow of major biological systems. Peptides influence things like immune regulation, growth hormone release, extracellular matrix production, nerve cell growth and migration, and much more. Peptides are the keys to starting and stopping major biochemical cascades and, as such, are of the utmost importance to proper biological function.
It’s important to remember that we consume peptides on a daily basis. Eggs, milk, beans, meat, oats, and wheat all contain peptides, proteins, and various other biologically active molecules. In addition, many popular supplements, energy drinks, and health foods are enriched with peptides that help to improve body composition, boost energy, and aid digestion. Examples of common peptides found in everyday products include collagen and creatine.
Peptides are generally divided into groupings based on their function. For instance, there are antibacterial peptides, vaccine peptides, and anticancer peptides. Unfortunately, these peptide categories often overlap, which makes strict categorization difficult and confusing. For instance, brain peptides and immune peptides often overlap. The same is true of skin peptides and immune peptides as well as skin peptides and tendon peptides. Categorizing peptides by where they are located is an untenable approach because they are often found in various tissues.
Another way to categorize peptides that may be more useful is to consider their major actions. In that case, it would be useful to think about healing peptides, growth peptides, longevity peptides, fat-burning peptides, anti-inflammatory peptides, and so forth. While this approach is better than the above, it is still complicated by the fact that most peptides cross category boundaries. BPC-157, for instance, is a healing peptide and an anti-inflammatory peptide.
It is important not to get caught up in categories like “brain peptide” or “healing peptide” as they often don’t capture the entirety of a peptide’s biological activity. The better way to approach them is to look at the biochemical pathways they influence. Sermorelin acetate, for instance, influences the growth hormone (GH) pathway. This results in myriad effects including enhanced muscle growth, fat burning, telomerase stimulation, and more. If you understand the biochemical pathways that peptides interact with, it is simpler to categorize both their activity and their side effects, which is more useful than knowing what tissues they can be found in.
What Are Peptides Being Used For?
Peptides are increasingly used in everything from anti-aging products to cosmetics to medical treatments. Understanding peptides and their uses is critical not just for the informed consumer, but for the individual who wants to maximize health and thwart the effects of aging. There are a host of peptides that research shows are beneficial for various health concerns, but sometimes the sheer volume of information can be overwhelming. If you want to just cut to the chase to understand what the best peptides for health, read on to see how certain peptides can reduce inflammation, destroy microorganisms, slow the aging process, and promote wound healing.
What to Know About Peptides?
The most important thing to know about health peptides in 2021 is that they are critically important to just about every aspect of function and longevity. Simply put, peptides control the body. Research over the last several decades has helped to reveal that peptides are critical in modulating the aging process, controlling inflammation, fighting off infection, accelerating wound healing, boosting cognition, altering body composition, and much more.
It has taken modern medicine a while to come around to the idea that peptides are more than simple research novelties. In fact, peptides can optimize well-being by helping to restore balance to biological systems. A perfect example of this is sermorelin.
Research shows that the decline of growth hormone (GH) secretion that occurs with age is not just a consequence of aging, but a major driver of the aging process as well. Though this certainly raises a chicken-or-egg style conundrum, the research about GH supplementation is very clear. Restoring GH levels to more youthful standards via the use of peptides like sermorelin leads to a host of benefits that include increased muscle mass, reduced fat mass, improved cardiac function, improved memory and cognition, better sleep, and more1
Peptides like collagen, which is found in almost every skin cream on the market today, have been in use for a very long time. Others, like PT-141 and BPC-157, which have been researched for quite some time, have only recently caught the attention of the world at large. The next several decades are likely to witness an explosion in the popularity of peptides as more and more funding focuses on these versatile small molecules.
What Are the Benefits of Health Peptides?
Research in both animal and human models shows that health peptides can have a host of beneficial effects. Examples of those effects include:
Research in both animal and human models shows that health peptides can have a host of beneficial effects. Examples of those effects include:
• Reduced inflammation2,3
• Enhanced wound healing4
• Reduced scar formation5
• Increased muscle mass and strength6,7
• Increased rate of fat burning8
• Improved insulin resistance9
• Increased bone strength and density10
• Improved immune function11
• Improved sleep12
• Improved memory and concentration13,14
• Better skin tone and elasticity15–17
Slowing the Aging Process
A handful of peptides, including sermorelin and epithalon, have been shown to alter the aging process at the level of DNA. These peptides activate an enzyme, called telomerase, that protects and repairs the end caps found on DNA (called telomeres). The degradation of telomeres over time is one of the primary signals that cells use to determine if they should divide and grow or not. If telomeres become too short, then cells stop dividing and tissue health declines. Peptides like sermorelin, by protecting telomeres, slow down the rate of tissue decline18,19
Of course, there are other ways to slow down aging such as preventing DNA damage in the first place. Peptides that reduce oxidative damage include sermorelin, epithalon, ipamorelin, CJC-1295, BPC-157, and more. These peptides are anti-oxidants and prevent the kind of damage that leads to cancer, heart disease, dementia, and other diseases of aging2,20,21
Finally, it is possible to slow down the appearance of aging separate from actually slowing the aging process itself. Many peptides can have this kind of impact including all of the peptides listed above as well as others like collagen, melanotan, and PT-141. Many of these peptides can reduce the appearance of wrinkles, improve skin elasticity, boost extracellular matrix production, improve body composition, and even improve skin tone.
Faster Wound Healing
Peptides can improve wound healing by influencing the growth hormone axis, boosting cell migration rates, reducing inflammation, and increasing the deposition of extracellular matrix components. A number of peptides such as VIP, KPV, BPC-157, sermorelin, and hexarelin have these abilities. Research shows that these peptides can improve the strength of wounds and reduce scaring.
BPC-157 is widely known for its healing properties, particularly for its ability to speed up the rate of tendon healing. Tendons are notoriously slow to heal, but research shows that BPC-157 not only speeds up the process, but actually makes it more effective as well. Tendons treated with BPC-157 heal stronger than those treated with a placebo4,22–25
Other peptides, like TB-500 and KPV, have anti-microbial properties that help to ensure sterile wound healing. Infection is well-known to complicate healing, so any factor that helps to limit infection will have an impact on the rate of wound healing26,27
Still other peptides increase the rate of blood vessel growth to help get nutrients and cells to the site of injury faster28
. There are myriad ways that health peptides influence the both the rate and degree of wound healing. There is a great deal of research into how these peptides impact healing in the setting of chronic disease like diabetes and other immune system compromising conditions.
Building Lean Body Mass
There are three ways to improve lean body mass: build muscle, burn fat, or build bone. Promoting the shift to lean body mass is an excellent way to improve health by reducing the risk of serious chronic diseases like diabetes and heart disease.
As it turns out there are a number of peptides that can perform any one of these functions that promote lean body mass and still others that can achieve all three. Sermorelin, CJC-1295, GHRP-2, and others affect the GH axis and cause increases in bone density and muscle mass while helping to burn fat29
. Ipamorelin has similar properties, but also has enhanced bone-strengthening effects. This has led to it being investigated as a potential treatment for osteoporosis10
Peptides like AOD-9604 and Tesofensine are targeted fat burners and though this can help to shunt resources toward bone and muscle building, they are primarily fat burning peptides8,30
. Combined with exercise and appropriate diet, these peptides can not only lead to substantial fat loss, but to improvements in blood glucose levels, insulin resistance, and glucose tolerance as well31
Simply put, a host of health peptides have been revealed through research to help shift the balance toward lean body mass and thus improved general health. There is ongoing research to understand not just how these peptides can be used therapeutically, but how they can be used to further research and understand the mechanisms that control body composition and identify root causes of conditions like the metabolic syndrome.
Summary of Peptides
Peptides are naturally present in the foods we consume and are often added to supplements, energy drinks, and fitness products to boost their effectiveness and improve health. Peptides for health have a variety of uses and can influence the biochemical pathways that control growth, body composition, cognitive function, immune response, and longevity.
Research into peptides is ongoing and continues to uncover not just beneficial properties of these short proteins, but improved means of storing, transporting, and administering them. The next decade will likely be filled with new insights into the power of peptides and their abilities to alter biochemistry in ways that stave off disease, dysfunction, and even death.
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