Your body cant produce L-methionine, so you must get it from your diet or supplements.
People often take them to treat various health conditions, but more research is needed to support these uses.
That means some supplement products may not contain what the label says.
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Our bodies cannot produce it.
L-methionine may be beneficial for various health conditions.
However, many of these are not well-supported by scientific evidence.
Below is a look at some of the better-supported uses of L-methionine.
No supplement is intended to treat, cure, or prevent disease.
Acetaminophen, or Tylenol, is a common, over-the-counter (OTC) pain reliever.
Reduced Cancer Risk
L-methionine has been studied for its role in cancer risk.
However, the results are conflicting.
In lab studies, it has been shown to be effective in liver cancer cells as well.
However, these findings have not always been replicated in studies examining the relationship between L-methionine and cancer.
In fact, some studies have shown that L-methioninerestrictionmay lead to a lower risk of cancer.
A review from 2020 noted that L-methionine is an integral part of the growth cycle in certain types ofcancercells.
According to the review, evidence that L-methionine restriction may inhibit cancer cell growth is growing.
Until then, L-methionine should not be used for this purpose.
The neural tube develops in the third and fourth weeks of pregnancy.
It eventually forms the baby’s brain, skull, spinal cord, and backbones.
Neural tube defects result from the tube not closing properly.
Examples includespina bifida,anencephaly, and encephalocele.
Protection Against Liver Damage
L-methionine may help improve liver damage, especially when used alongside other treatments.
A 2020 review found that L-methionine supplementation may help reduce the risk of liver damage.
L-methionine is found in the greatest amounts in animal foods.
It is present in plant-based foods in smaller amounts.
L-Methionine Supplements
L-methionine supplements are available in capsule form.
You may also find supplements that contain L-methionine and other nutrients, like various amino acids.
These also tend to be sold as capsules.
Vegan versions of L-methionine supplements are available.
If you are vegan or vegetarian, choose a plant-based L-methionine supplement.
Dosage
There is no standard dose for L-methionine supplements.
However, there is a recommended daily intake of L-methionine from food and other sources.
This gives you all thesulfuryour body needs to build important proteins.
Talk with your healthcare provider about using L-methionine safely before you jump in taking supplements.
Storing L-Methionine
Improper storage of L-methionine supplements can cause spoiling.
L-methionine should be stored in a cool, dry place that is not in direct sunlight.
It is best to keep L-methionine supplements in the air-tight container they came in.
L-methionine supplements should be discarded once they reach the expiration date listed on the packaging.
Due to the possibility of overdose, keep L-methionine supplements out of reach of pets and small children.
L-methionine side effects can be mild or severe.
L-methionine is thought to be safe for most people to take at normal doses.
Oftentimes, side effects are more likely when supplements are taken incorrectly or if the dose is too high.
This helps prevent high levels of homocysteine in the blood.
Severe Side Effects
In general, L-methionine is thought to be safe.
However, severe side effects are possible if it is taken incorrectly.
These may include highcholesterol levels, which increases the risk of cardiovascular disease, heart attack, andstroke.
Although extremely rare, it is possible to overdose on L-methionine.
In addition, high levels of L-methionine have been associated with an increased risk of diabetes.
Hyperhomocysteinemia
Taking too much L-methionine can causehomocysteinelevels to rise (hyperhomocysteinemia).
Homocysteine is a potentially dangerous compound.
It is a known risk factor for cardiovascular disease.
Too much L-methionine has been linked to not only hyperhomocysteinemia but alsooxidative stress.
Together, these two factors may speed up the aging process, leading to memory problems and cognitive deficits.
This increases the risk of neurodegenerative diseases like Parkinson’s and Alzheimer’s.
Who Should Not Take L-Methionine
L-methionine may not be safe for everyone.
However, the research looking into this claim is not strong.
L-methionine may be safe for infants and children, but consult your child’s healthcare provider about using supplements.
Single amino acid supplements like L-methionine can lead to growth problems in children.
Summary
L-methionine is an essential amino acid, which means we must consume it.
It is found in animal and plant sources.
It is one of just two amino acids that contain sulfur and may be helpful for some health concerns.
However, research that backs up most of these health claims is lacking.
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