L-Taurine: Cardiovascular Support, Metabolic Health, Usage Tips, and Safety Considerations
Taurine is a conditionally essential amino sulfonic acid found in the brain, heart, retina, and skeletal muscle. Unlike most amino acids, it is not used to build proteins; instead, it supports cell membrane stability, calcium signaling, bile acid conjugation, and antioxidant defense. In food, taurine occurs naturally in meat and seafood; it is also added to many energy drinks....
L-Theanine: Calm Focus, Stress Relief, Sleep Support, Dosage and Side Effects
L-theanine is a non-protein amino acid found naturally in tea leaves (Camellia sinensis) and certain mushrooms. People reach for it to take the “edge” off stress without feeling sedated, to sharpen attention (especially when paired with caffeine), and to support sleep quality. Unlike many calming ingredients, L-theanine acts fast—often within 30–60 minutes—by promoting alpha brain waves linked with a...
L-Threonine: Gut Barrier Support, Immune Function, Daily Intake, and Side Effects
L-threonine (often shortened to threonine) is one of the nine essential amino acids your body cannot make on its own. You get it from food proteins and, in some cases, from supplements. Because threonine is abundant in mucin (the protective gel that lines your gut), and is built into structural proteins and enzymes throughout the body, it is closely...
L-Tryptophan: Sleep Support, Mood Effects, Optimal Timing and Dose, and Side Effects
L-tryptophan (often shortened to “tryptophan”) is an essential amino acid—meaning your body cannot make it and must get it from food or supplements. It is best known as the raw material for serotonin and melatonin, two signaling molecules that influence mood, sleep, appetite, and the 24-hour body clock. Beyond neuromodulation, tryptophan feeds into the kynurenine pathway that produces nicotinamide...
L-Tyrosine: Benefits for Working Memory and Vigilance, Use Cases, Dosage, and Interactions
L-tyrosine is a conditionally essential amino acid that your body uses to build catecholamine neurotransmitters—dopamine, norepinephrine, and epinephrine—as well as thyroid hormones and skin pigments (melanin). Because stress, sleep loss, heat, cold, and heavy cognitive load can temporarily drain catecholamine signaling, tyrosine has been studied as a short-term “resilience nutrient.” In practical terms, the right dose taken at the...
Lugol’s iodine: What It Is, Real Benefits, Safe Dosing, and Risks Explained
Lugol’s iodine is a simple mixture of elemental iodine (I₂) and potassium iodide (KI) dissolved in water. Created in 1829 by French physician J. G. A. Lugol, it remains a pharmacy staple thanks to iodine’s unique chemistry: in the body, iodide fuels thyroid hormone production; in medicine, concentrated iodine temporarily tames an overactive thyroid; in public health, iodide protects...
Lumbrokinase: Fibrin Support, Stroke Recovery Insights, How to Use It, and Safety Considerations
Lumbrokinase is a group of fibrin-targeting enzymes originally isolated from earthworms and now produced under modern quality controls. People turn to it to support healthy circulation, help maintain blood flow, and complement medical care for clot-related conditions under professional supervision. What makes lumbrokinase distinct is its high fibrin specificity: it works where fibrin exists, which is why it’s often...
Lupeol: Anti-Inflammatory and Antioxidant Properties, Evidence, Dosage, and Side Effects
Lupeol is a plant-derived triterpenoid found in mango, olive, aloe, and many medicinal herbs. Over the past two decades it has drawn wide attention for its anti-inflammatory, antioxidant, and cytoprotective actions across skin, metabolic, cardiovascular, and neurological models. Researchers also study lupeol for selective anticancer effects in cells and animals, and for its potential to modulate master signaling hubs...
Lupin protein: Cardiometabolic Benefits, Daily Dosage Guidelines, Uses in Cooking, and Side Effects
Lupin protein has moved from niche ingredient to serious contender among plant proteins. Milled from the seeds of Lupinus species—most commonly white (Lupinus albus) and narrow-leafed (Lupinus angustifolius)—it delivers 35–45% protein with notable fiber and minimal starch. Its storage proteins (the conglutin family) and naturally high arginine content give it a unique profile: supportive of healthy blood lipids, filling...
Lutein: Eye Health Benefits, How to Use It, Recommended Dosage, and Side Effects
Lutein is a yellow-orange carotenoid concentrated in the macula—the tiny, central area of the retina responsible for sharp, detailed vision. Because the body cannot make lutein, we rely on foods like spinach, kale, and egg yolks or on supplements. Interest in lutein has grown for three practical reasons: it accumulates in the eye where it filters blue light; it...
Luteolin: Neuroinflammation Support, Evidence-Based Benefits, How to Use, and Risks
Luteolin is a naturally occurring flavonoid found in foods like celery, parsley, thyme, green peppers, and chamomile. Over the last decade, it has drawn interest for its broad anti-inflammatory, antioxidant, and mast-cell–stabilizing actions. Early clinical trials and many preclinical studies suggest potential roles in calming allergic responses, supporting brain health under stress, and easing neuroinflammation. In supplements, luteolin typically...
L-Valine: Evidence-Based Benefits for Athletes, How to Use, Dosage, and Risks
L-valine is one of the three branched-chain amino acids (BCAAs), alongside leucine and isoleucine. As an essential amino acid, your body cannot make it; you must get it from food or supplements. In muscle, valine is used directly as fuel during exercise and serves as a building block for new proteins. In the brain, it competes with tryptophan and...
Lychee fruit extract: Visceral Fat Support, Muscle and Circulation Benefits, Dosage Guide, and Side Effects
Lychee fruit extract is best known for a standardized form called “oligomerized polyphenols” (often marketed as Oligonol), made from Litchi chinensis. It concentrates small, easily absorbed flavanols—primarily catechin and epicatechin oligomers—along with ancillary phenolics found in the fruit’s red pericarp. Early research suggests potential support for abdominal fat reduction, better peripheral circulation in people sensitive to cold hands and...
Lycopene: Evidence for Skin and Cardiovascular Support, Best Sources, Dosage, and Risks
Lycopene is the red carotenoid that gives tomatoes, watermelon, and pink grapefruit their color. Beyond appearances, it acts as a potent singlet-oxygen quencher and lipid-phase antioxidant, accumulating in tissues such as the skin, liver, and prostate. Research links lycopene intake to support for photoprotection (helping skin tolerate sun exposure), cardiovascular risk factor management in select contexts, and prostate health....
Lycopus virginicus: Thyroid-Calming Benefits, How to Use, Dosage, and Safety
Lycopus virginicus—commonly called bugleweed—is a traditional North American mint-family herb used for calming symptoms that often accompany mild or early hyperthyroidism, such as a racing heart, heat intolerance, tremor, and restlessness. Practitioners have long paired it with closely related species (for example, Lycopus europaeus) for “vegetative” complaints: palpitations, nervousness, irritability, and sleep disruption. Modern laboratory and animal data suggest...
Lythrum salicaria: Evidence for Gut Support, Best Preparations, Recommended Dosage, and Side Effects
Known as purple loosestrife, Lythrum salicaria is a wetland plant with a long history in European folk and official medicine for soothing acute diarrhea, calming inflamed mucous membranes, and supporting skin healing. Today, interest is returning thanks to modern analyses that spotlight its dense polyphenol profile—especially ellagitannins such as vescalagin and castalagin—and focused lab studies that link these compounds...
