L-Arginine Plus by Thorne

If you’re looking for L-arginine for blood flow because your hands and feet run cold, your workouts feel flat, or your blood pressure is high-normal, this fits. It’s also useful if your Homocysteine (an irritant to blood vessels) runs high or your hs-CRP (an inflammation marker) is up. Athletes who want better exercise tolerance and older adults with stiffer arteries tend to notice the most. If you already eat a lot of nuts, seeds, and beans, you still may benefit because this is a clinically dosed, sustained-release form.

L-arginine is the raw material your blood vessels use to make nitric oxide (the gas signal that tells arteries to relax). A sustained-release form smooths out the rise and keeps levels steadier through the day. Vitamin C helps preserve nitric oxide once it’s made, while 5-MTHF folate supports homocysteine metabolism, which is tied to healthier vessel lining. Decaffeinated green tea phytosome and trans-resveratrol deliver polyphenols that modestly lower hs-CRP in responders, and R-lipoic acid can improve insulin sensitivity, a plus if fasting glucose or insulin run high.

Take three capsules twice daily, ideally split 12 hours apart, to match how nitric oxide signaling works across the day. You can take it with or without food; use a meal if you notice stomach upset. Expect circulation changes within 2 to 4 weeks, with exercise endurance or warm extremities often noticed first. If your goal is blood pressure, give it 4 to 8 weeks and track at home while also watching hs-CRP or Homocysteine if those were concerns.

Avoid if you take nitrates for chest pain (nitroglycerin, isosorbide) or riociguat, as combining vasodilators can drop blood pressure too far. Use caution with sildenafil or tadalafil, and with antihypertensives—monitor pressure. If you have diabetes on medication, R-lipoic acid can lower glucose, so track readings. History of cold sores or genital herpes can flare with high arginine, so reconsider. Skip after a recent heart attack, and check with your clinician if you have advanced kidney disease or very low blood pressure.

Does it lower blood pressure? Modestly in many, especially if your baseline is elevated, but it’s an add-on to lifestyle, not a replacement. Is there caffeine here? No—the green tea is decaffeinated. Can vegans use this? Yes, and the 5-MTHF form of folate is the active type. Will it help cholesterol? It doesn’t lower LDL on its own; focus on Triglycerides, hs-CRP, and Homocysteine for signals it’s helping vascular health.