Category Archives: Amino Acids for Health Issues

L-Carnitine Supplement Could Treat Heart Disease

An animal study has identified a potential new therapeutic option for treating cardiac fibrosis: L-carnitine supplementation. Could L-carnitine prevent the development of heart failure?

Researchers (Y Omori, T Ohtani, et al), at the Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Japan, developed an animal study to analyze potential new treatments for heart failure—specifically heart failure with preserved ejection fraction (HFpEF) in hypertensive heart disease.

Hypertensive heart disease is caused by hypertension, or high blood pressure. Hypertensive heart disease with heart failure is a serious condition, which can lead to ischemic heart disease and heart attacks. Heart disease is leading cause of death worldwide, according to the World Health Organization.

The researchers were aware that prognosis of heart failure with preserved ejection fraction is poor. They knew that hypertension causes decreased free-carnitine levels in the heart. Would L-carnitine supplements have an effect?

Carnitine is a non-essential amino acid, synthesized in the human body from the amino acids lysine and methionine. Carnitine is also found in food, especially red meat and dairy products. L-carnitine is simply the biologically-active form of carnitine.

Carnitine has a substantial antioxidant effect, which greatly benefits health by preventing free radical damage. The researchers hoped that the carnitine supplements would also combat hypertension.

L-carnitine treatment and heart failure study

Rats were given a high-salt diet, which models hypertensive heart failure. Their free carnitine levels were measured, and were found to be low in the left ventricle of the heart. The rats were then given L-carnitine supplements.

This L-carnitine treatment had a significant impact. It restored the levels of carnitine in the chambers of the heart, and even reversed fibrosis. Cardiac fibrosis is a thickening of the heart valves, which is often found in heart failure.

The affect L-carnitine has on reversing, or thinning, the level of cardiac fibrosis means that L-carnitine could become a therapeutic option for treating hypertensive heart disease in the future.


Can Carnitine Help Enhance Exercise Performance?

Feel like your workouts aren’t going so well? Perhaps carnitine supplements may be of use to reach your fitness goals. 

The compound carnitine is synthesized from amino acids lysine and methionine. Its role is to transport fatty acids from the cytosol to the mitochondria to help break down lipids and fats in order to create metabolic energy. The majority of carnitine is found in skeletal muscle, helping maintain co-enzyme A by creating acetylcarnitine during high intensity exercise.

In a study done by Maastricht University in the Netherlands, researchers Benjamin Wall, Francis Stephens, Dumitru Constantin-Teodosiu, Kanagaraj Marimuthu, Ian Macdonald and Paul Greenhaff hypothesized that chronic ingestion of L-carnitine and carbohydrates would increase skeletal muscle total carnitine content in healthy participants, generating various positive metabolic effects of muscle carnitine loading that would lead to an improvement in high intensity exercise performance.

For the double-blind experiment, 14 healthy, athletic male participants were used. Two weeks before the start of the trial, the participants were pre-tested for maximal oxygen consumption so individual exercises could be determined to use 50% and 80% of their maximal oxygen uptake.

For the trial phase, the subjects were to undergo the experimental protocol on three occasions, 12 weeks apart. Blood samples were collected to assess blood glucose, serum insulin and plasma total cholesterol concentration. The participants exercised for 30 mins on a cycle ergometer at 50% maximal oxygen intensity, followed by 30 mins of exercise at 80% maximal oxygen consumption. Immediately after the exercises, the participants performed a 30-min work output performance test to measure endurance and performance.

After the first experimental visit, the participants were randomly assigned to two treatment groups. The control group consumed 700 mL of a beverage containing 80 grams of carbohydrate polymer twice daily for 168 days.

The experimental group consumed the same amount of beverage but with an additional 2 grams of L-carnitine tartrate, at the same frequency. On every visit, the same exercise protocol was conducted as the first visit. Blood samples and muscle biopsy samples were also collected from the participants throughout.

The effect of L-carnitine on muscle total carnitine content and exercise performance

After evaluating the data, the researchers found that after 24 weeks muscle total carnitine content was 30% more in the carnitine group than the control, meaning a 21% increase from baseline.

This is the first study conducted that demonstrated muscle carnitine content can be increased by dietary intake in humans. It also showed carnitine plays a role in the fuel metabolism of skeletal muscle, dependent on intensity of exercise.

The researchers also found that work output was 35% greater for the carnitine group compared to the control, by the end of the trial. This represented a 11% increase from baseline measures. By increasing muscle total carnitine content, muscle carbohydrate use is reduced during low intensity exercise. For high intensity exercise, muscle carnitine reduces muscle anaerobic energy due to its enhanced generation of glycolytic, pyruvate dehydrogenase complex and mitochondrial flux.

Working as a combination, these metabolic effects lead to a reduced perceived effort but increased output, helping improve exercise performance.


Glutamine Deprivation May Slow Pancreatic Cancer

Tumor growth in pancreatic cancer patients may be slowed using glutamine. Glutamine is an amino acid, which is one of the building blocks of proteins. Although it is typically considered a non-essential amino acid (meaning the body may make it on its own), glutamine is technically a conditionally essential amino acid. The term “essential” means that it must be gotten through the diet, so this amino acid is—in certain circumstances—acquired via intake of food.

Glutamine, which is the most abundant amino acid in the human body, plays a role in cancer tumor growth; so depriving the cancer cells of glutamine may hold the key to slowing the spread of cancer of the pancreas, a study shows.

Study on pancreatic tumor growth and glutamine

At the Division of Genomic Stability and DNA Repair, Department of Radiation Oncology (part of the Dana-Farber Cancer Institute) in Boston, Massachusetts, a group of researchers and doctors, J Son, CA Lyssiotis, et al., have investigated just how the amino acid glutamine is involved with the KRAS-regulated metabolic pathway, which is part of the cause of tumor growth within the pancreas itself.

The researchers studied the metabolism of cancer cells and glutamine dependencies since, unlike normal cells, the cells within cancer tumors maintain their own type of metabolism. They said that “an increased use of the amino acid glutamine to fuel anabolic processes. Indeed, the spectrum of glutamine-dependent tumors and the mechanisms whereby glutamine supports cancer metabolism remain areas of active investigation.”

Because human pancreatic cells use a non-standard pathway, which identifies ductal adenocarcinoma (PDAC) cells, most cells use “glutamate dehydrogenase (GLUD1) to convert glutamine-derived glutamate.” What this means is that the PDAC cells “are strongly dependent … as glutamine deprivation or genetic inhibition of any enzyme in this pathway leads to [a] series of reactions [that] results in a pronounced suppression of PDAC growth in vitro and in vivo.”

The scientists established that because the glutamine metabolism is reprogrammed and “mediated by oncogenic KRAS, the signature genetic alteration in PDAC [represses] key metabolic enzymes in this pathway.”

With the PDAC pathway and pancreatic cells being dispensable, the glutamine in normal cells then becomes a possible new therapeutic approach in treating pancreatic tumors in humans. Hopefully more will be forthcoming on this new technique in the near future.


Lysine Deficiency in Vegans and Vegetarian Diet

Lysine is an amino acid that is very often found in deficient levels within vegetarians, and especially vegans. Lysine is found in abundance within meats and other protein foods, such as beef, turkey, pork, lamb, chicken, as well as fish and eggs. Since vegans and vegetarians do not typically consume animals or their products, the levels of lysine are sometimes dangerously low. How can this be helped?

Vegetarian foods that are highest in lysine

Although meat contains all 22 common amino acids, including lysine, it is not a product that vegetarians—and especially vegans–consume, Below are some suggestions for a high-lysine diet and the kind of protein foods that can provide this important amino acid.

Lysine from protein foods should include eating 1.0 to 1.1 grams/kilogram of body weight daily (for adults). This is especially important if you are over the age of 60. Vegetarian sources of lysine-containing foods, for the vegetarian that allows no mammals, but do allow some animal products, include these…

Ovo-vegetarians can eat eggs, which have all 22 amino acids, including plenty of lysine.

Pescetarians eat fish, which is also an excellent source, plus have heart-healthy oils for cardiovascular health.

Lacto-vegetarians eat milk / dairy products, which contain lesser amounts of this amino acid, but definitely more than vegetable sources.

Vegan foods high in lysine

There are definitely some high-lysine vegan foods that are available for people who do not eat any animal products whatsoever. Vegetable sources for lysine, which should be eaten daily, include:


Legumes include soybeans, and products of soybeans (such as tempeh, tofu, soy milk, soy protein, etc.), and beans (garbanzo, pinto, black beans, and other dry beans) and their products (refried beans, hummus, falafel), and peas (split, green peas, black-eyed, etc.).

Nine essential amino acids cannot be produced by the body, so must be taken in via food or through supplementation. Legumes and seitan—per serving—have the highest amount of lysine. In fact, the highest vegan foods also include tempeh, tofu, soy meats, lentils, and seitan.

Lysine is also found in fairly decent quantities within quinoa and pistachios.

The US RDA recommendation for lysine from proteins is about 1g/kg protein for children, and .8g/kg for people aged 18-59, and up to 1.3g/kg protein for people over 60.

Lysine, since it is an amino acid, can also be taken as a dietary supplement from the health food store or drug stores. Overall, there is no reason why one has to give up their vegan or vegetarian lifestyle just because they are deficient in this aminio acid. There are ample ways to include it via foods or supplementation into your daily regimen.


Chronic Liver Disease Shows Amino Acid-Sulphur Deficiency

Turns out that your liver can benefit from the sulphur-containing amino acids methionine and cysteine. Health benefits of amino acids such as these are excellent, but this is especially true for those with liver disease. As it turns out, those with chronic liver disease actually show a pattern of sulphur deficiency, so both cysteine and methionine may help with this.

Advanced liver disease and methionine / cysteine amino acids

In advanced or chronic liver disease, the metabolism of the sulphur-containing aminos, such as methionine and cysteine, are is impaired (no difference in the amino acid taurine, however).

In a study by P Almasio, G Bianchi, et al., at the Clinica Medica R, Università di Palermo, in Italy, the researchers published their discoveries based on 60 people who had chronic liver disease. The results show a pattern of amino acid deficiency in these patients.

10 of the subjects were used a control because they were healthy, but the other 50 patients had chronic liver disease, which was proven via biopsy.

The breakdown of their liver disease impairments

Hypermethioninemia (an extreme amount of methionine) was present in only these cases:

10 cases compensated cirrhosis
10 cases decompensated cirrhosis

Plus there were:

30 cases chronic hepatitis

The results of this clinical trial showed cysteine, a metabolite of methionine metabolism, was “markedly reduced in patients with compensated chronic liver disease, while in advanced cirrhosis its concentration was within the normal range.”

Methionine is an essential amino acid, which means you can only get it through diet, particularly protein foods such as meats (chicken, beef, pork, lamb, plus fish and eggs). Also, cysteine is a non-essential amino acid, which means the body can produce this amino acid on its own. No differences were observed (in plasma levels) for the amino acid taurine between groups.

What was observed was how sulfur-containing amino acid metabolism was deranged and “possibly located at various steps along the trans-sulphuration pathway, is also present in mild forms of chronic liver disease.”

What this means is that a key marker for those with chronic liver disease is that sulphur-containing amino acids are deficient. This can be true for people suffering from decompensated cirrhosis), or hepatitis.

The study did not explain whether supplementing intake with cysteine or methionine would affect the—chronic liver disease–patients in a positive way or not, but it is good to know that both of these amino acids are in ample amounts when associated with healthy livers, yet levels are abnormal in diseased livers.


Prevent Prostate Cancer with Three Amino Acids?

Three specific amino acids may aid in the prevention of prostate cancer according to a study. The three aminos include methionine, phenylalanine, and tyrosine. During protein synthesis by the body, the amino acids tyrosine, methionine, and phenylalanine are utilized. Restriction of these amino acids depends on glucose metabolism, which when altered aids in cell death of cancer cells within human prostate cancer, and may aid in preventing prostate cancer.

Study linking amino acids and prostate cancer prevention

YM Fu, H Lin, et al., did a study at the Department of Pharmaceutical Sciences at Washington State University said that it is selective amino acid restriction of tyrosine and phenylalanine, plus methionine or glutamine that target mitochondria in cells that are linked to prostate cancer cell death.

Glucose metabolism modulation is tied to the process and “crucial switches connecting metabolism and these signaling molecules to cell survival during amino acid restriction” become target factors preventing prostate cancer, say the researchers.

Second study on prostate cancer and amino acids

Another study by YS Kim from Washington State University showed an identification of molecular targets regarding specific amino acid dependency and how it modulates specific kinds of prostate cancer cells. To find out how the amino acids can prevent prostate cancer, they investigated if restriction of tyrosine, phenylalanine, and methionine could inhibit the growth and metastasis of prostate cancer.

Kim progressed outward in this field of research because of the “underlying the anticancer activity of tyrosine/phenylalanine and methionine restriction. This is especially important research since there still is no satisfactory drug for treatment of androgen-independent, metastatic human prostate cancer.”

Even though further research is needed regarding the amino acids phenylalanine, tyrosine, and methionine for prostate cancer prevention, it has expanded avenues for antimetastatic, anti-invasive, apoptosis-based therapies for the preventing prostate cancer.

Prostate cancer, being one of the major cancers that kill men in the North American continent, is the reason why males should be regularly screened for this deadly disease.


Part 1: Alzheimer’s Prevention? Special Foods and Cysteine and Glutathione Levels

The amino acids cysteine and glutathione play a role, it seems, in preventing the onset of Alzheimer’s. Evidently, according to a study by SS Karuppagounder, JT Pinto, et al., in their study on “Dietary supplementation with resveratrol reduces plaque pathology in a transgenic model of Alzheimer’s disease” from the Department of Neurology and Neurosciences, at the Burke Medical Research Institute, in White Plains, New York, the amino acid levels of cysteine and glutathione are affected in Alzheimer’s patients by the same types of chemopreventive agents (cancer-preventing foods) that cancer patients would eat to help prevent cancer.

One food constituent in particular was studied by the researchers—Resveratrol. Resveratrol is a polyphenol that is found in peanuts, pomegranates, soybeans, and especially red wine. People have heard for years about resveratrol being good for the heart, but evidently it is good for the brain as well, including other neurodegenerative diseases, including Alzheimer’s disease.

Even though resveratrol was fed to the hosts for forty-five days, it was not detectable in the brain, yet plaque formation in the regions of the brain were diminished. The majority of the diminished brain-plaques were “observed in medial cortex (-48%), striatum (-89%) and hypothalamus (-90%). … However, brain glutathione declined 21% and brain cysteine increased 54%.”

Cysteine and Glutathione’s role in chemopreventive agents

There is a list of foods, called chemopreventive agents, which help prevent cancer, that also may help with oxidative stress, destroying free radicals that also cause DNA damage, or help prevent plaques in the brain of people who may otherwise be developing Alzheimer’s disease (AD). I will cover some of these agents first:

According to one source, there are two such agents that have carcinogen-detoxifying activity that “might be achieved by combination of an agent such as N-acetyl-l-cysteine (NAC), which provides substrate for glutathione (GSH) synthesis, with agents such as oltipraz or garlic/onion disulfides, which enhance GSH S-transferases (GST).”

The food constituents will be listed further in our next section…

CONTINUE TO Part 2: Alzheimer’s Prevention? Special Foods and Cysteine and Glutathione Levels 


Part 2: Alzheimer’s Prevention? Special Foods and Cysteine and Glutathione Levels

CONTINUED FROM Part 1: Alzheimer’s Prevention? Special Foods and Cysteine and Glutathione Levels, where we covered the research done on Alzheimer’s patients that found Resveratrol affected cysteine and glutathione levels, raising the former, and reducing the latter, and their connection to reduced brain plaques. 

Chemopreventive agents that help cancer patients may also help Alzheimer’s patients…

Chemopreventive agents (food constituents), cysteine, and glutathione

Food-derived chemopreventive agents may help when used by normal-risk populations with long-term use. According to a study by GJ Kelloff, JA Crowell, et al., and their assessment, there are 40 promising agents and food combinations “being evaluated clinically as chemopreventive agents for major cancer targets including breast, prostate, colon and lung. Examples include green and black tea polyphenols, soy isoflavones, Bowman-Birk soy protease inhibitor, curcumin, phenethyl isothiocyanate, sulforaphane, lycopene, indole-3-carbinol, perillyl alcohol, vitamin D, vitamin E, selenium and calcium.” Many of these agents are available to purchase online from supplement vendors such as:, and

Additionally, some natural sources that have anti-cancer, antioxidant, anti-tumor, antibacterial, antifungal, and anti-viral constituents includes a huge variety of medicinal mushrooms like reishi, maitake, cordyceps, shiitake, and so on. Lion’s mane mushroom (Hericium erinaceus), in particular, boasts boosting of cognitive function, memory, and learning in those who take them regularly, as well as immune-enhancing health benefits.

Many amino acids are also known to be brain food. Cysteine and glutathione were the aminos that were implicated in the first study mentioned above, although it was the higher levels of cysteine and lowered glutathione that helped the plaque in Alzheimer’s patients.

Cysteine is a semi-essential (normally listed as a non-essential) amino acid. When it is used as a food additive, it has the E number “E920”. In rare cases this amino acid may be important for infants or the elderly, or for people with malabsorption syndromes or metabolic disease. As long as enough methionine is available, cysteine can usually be synthesized by the body.

Cysteine is found in protein foods like: beef, pork, poultry, eggs, and dairy, and in lesser amounts in plant sources such as garlic, onions, broccoli, red peppers, Brussels sprouts, granola/oats, wheat germ, or lentils.

The non-essential amino acid glutathione works as an important antioxidant in animals and plants, fungi and some bacteria, as well as archaea, preventing free radicals and peroxides damage. However, glutathione is not considered an essential nutrient since it can be produced by the body (outside of food) from the amino acids L-cysteine, L-glutamic acid, as well as glycine.

Interestingly, the sulfhydryl (thiol) group of the amino acid cysteine is actually the amino acid responsible for glutathione’s activity in the body. This is why they are connected. Cysteine limits glutathione synthesis in cells since glutathione is rare in foodstuffs.

Remember that in the original study on Alzheimer’s patients and reduced brain plaque formation, it was the connection of increased cysteine and decreased glutathione that may be the link. That study, according to the researchers, “supports the concept that onset of neurodegenerative disease may be delayed or mitigated with use of dietary chemo-preventive agents that protect against beta-amyloid plaque formation and oxidative stress.”

With this in mind, be aware of the fact that chemopreventive foods like Resveratrol in red wine, or garlic, not only may help prevent cancer or improve cardiovascular health, but also are connected to a reduction in Alzheimer’s disease rates due to how it affects amino acids cysteine and glutathione levels. Please check with your doctor before altering your diet.


Part 1: Aspartic Acid and Phenylalanine in Aspartame

What are aspartic acid and phenylalanine, and what are their roles as ingredients in the manmade product called aspartame? Is aspartame dangerous or linked to cancer? Many claims exist, but here are some facts and information on the subject, which you might want to consider.

First of all, aspartame is an artificial sweetener; it is known as NutraSweet® and Equal® as well as Spoonful, and Equal-Measure, and is claimed to be up to 200 times sweeter than sugar. Aspartame was, in 1981, approved for use in dry goods, and later in 1983 approved for carbonated beverages. Aspartame basically has three main ingredients: aspartic acid, phenylalanine, and methanol.

I will go briefly over these three ingredients below and then discuss their use in aspartame…

Aspartic acid

Amino acids are the building blocks of proteins, and aspartic acid, also known as asparaginic acid, is a non-essential amino acid. “Non-essential” means that it is not necessary to get this amino acid from food or supplements since the human body makes it on its own. Our bodies need and use aspartic acid within cells to help the body work, especially regarding nervous system functioning, and hormone production/release.


Phenylalanine is also an amino acid, but an essential amino acid, which means it can only be gotten from food (our body does not make it on its own). Phenylalanine is the precursor for the amino acid tyrosine, which acts as a neurotransmitter in our brain for signaling dopamine, norepinephrine (noradrenaline), epinephrine (adrenaline), and melanin (skin pigment).

Phenylalanine is also found in breast milk and is a necessary nutrient for newborn babies, which is why it is added to baby formulas. Phenylalanine is a nutritional supplement in food and drink products and is known for its antidepressant and analgesic effects.

All 22 common amino acids, including aspartic acid and phenylalanine, can be gotten from protein foods such as meats, fish, and eggs, and smaller amounts from dairy, legumes, nuts, and vegetables.


Where aspartic acid and phenylalanine are natural substances, and needed for proper bodily functioning, methanol is toxic to the human body. Methanol is known as wood alcohol, methyl alcohol, wood naphtha, or wood spirits and is a chemical produced mostly as a byproduct of the destructive distillation of wood. Modern methanol is produced industrially from hydrogen, carbon monoxide, and carbon dioxide. Methanol is simple as alcohols go, flammable, volatile, colorless, and sweeter than ethanol (drinking alcohol). Methanol is used for producing biodiesel, as a fuel, denaturant for ethanol, and is a greenhouse gas.

Ingesting large quantities of methanol causes it to be metabolized to formate salts and formic acid. These may cause coma, blindness, or even death, because they are poison to the central nervous system. Special emphasis on “large quantities.” Why? Keep reading…

CONTINUE TO Part 2: Aspartic Acid and Phenylalanine in Aspartame


Amino Acids as Anti-Inflammatory Pain Relief

Did you know that amino acids can be used for pain relief? People often will take over the counter painkillers like acetomenaphen (e.g., Tylenol), or anti-inflammatories like ibuprofen (e.g., Advil), but a natural source of analgesics with some anti-inflammatory effects include amino acids. Amino acids are known as the building blocks of proteins, but they serve many functions in the body, especially to the organs and brain, or even the muscles and nerves. Taking amino acid supplements can sometimes aid the body to ward off pain and inflammation, just like a natural painkiller.

There are a couple of studies that tested amino acids like L-isoleucine, which can act as an agent for pain relief, and so prostaglandin was studied to see the effectiveness of L-isoleucine for the analgesic (painkilling) and anti-inflammatory properties. In order to understand how this works we must understand how prostaglandin works…

Prostaglandins are lipid compounds that work on-site like Aspirin; however, they are enzymatically derived (from fatty acids). Although prostaglandins work in a variety of ways, one of them is by acting as an analgesic, or natural pain reliever. Analgesics help your body achieve analgesia—relief from pain.

When there is an injury or you are will, the prostaglandins (whether due to amino acids or medicine) do not get secreted from the gland, but instead are chemically made on-site so they can be used exactly where they are needed, such as to control or reduce inflammation.

Amino acids studied as analgesics (pain relievers)

One study by E Ricciotti and GA FitzGerald regarding prostaglandins showed that they can act as a natural painkiller and help reduce the anti-inflammatory response. The researchers said, “prostaglandins may function in both the promotion and resolution of inflammation.” But amino acids may also cause a bodily anti-inflammatory response.

In a different study, four amino acids were investigated. The scientists RN Saxena, VK Pendse, and NK Khanna “Orally administered L-isoleucine, DL-isoleucine and L-leucine [which] exhibited anti-inflammatory activity in many test models of inflammation except formaldehyde-induced inflammation. L-beta-phenylalanine inhibited carrageenan-induced oedema only.”

Interestingly, it was the L-isoleucine that showed an extended analgesic (painkiller) result. Meanwhile, DL-isoleucine did have a short-lasting effect.

Unlike some supplements, the amino acids did not cause gastric ulceration nor did it promote acute toxicity in the doses that suppressed inflammation effectively. The researchers’ assessment on the painkilling amino acids included that the “anti-inflammatory activity seems to be related with interference with the action and/or synthesis of prostaglandins and deserves further intensive study.”

Of course, it depends on the problem and which amino acids you can use to act as a natural painkiller against it, so more research will continue in this area as time progresses.