The most common hawthorn side effects include positive benefits like lower blood pressure and improved cardiovascular health as well as detrimental effects like drowsiness and heart palpitations. Taken for generations as a botanical cure-all, hawthorn is also credited with lowering bad cholesterol, easing the pain of gout and other forms of arthritis, and curing insomnia. It is also believed to fight off diarrhea and throat infections. The superstitious believe it can also fight off demonic spirits.
Laden with antioxidants which fight aging, the herb produces its positive hawthorn side effects through a type of antioxidant known as bioflavonoids. The most effective bioflavonoids behind the hawthorn side effects are vitexin, oligomeric proyanidins, and hyperoside. Bioflavonoids are natural pigments which give the hawthorn plant its color. When digested, chemicals in these pigments offer protection to the heart by improving artery blood flow, halting irregular palpitations and strengthening the heart muscles.
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One key reason for the heart-related hawthorn side effects is that the herb interferes with enzymes in the body which weaken heart muscles. The supplement, therefore, is able to preserve heart muscle tone, enabling the heart to pump more vigorously. This benefit often attracts athletes and other highly active people who take the supplement to protect the heart during vigorous activities. It is also a favorite of elderly people who have suffered heart disease.
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Another bioflavonoid known as rutin delivers hawthorn side effects for the circulatory system. Rutin has the ability to make blood vessels more flexible so that they can widen more as they accommodate circulating blood. The effect of having blood flow through wider pathways with less pressure means that hypertension is often reduced, blood gets more oxygen, and organs, particularly the heart, get more blood. Alternative medicine doctors often recommend this herb to people suffering from chest pains due to a lack of oxygen and restricted blood flow to the heart.
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The berries, leaves, and flowers of the hawthorn shrub are crushed, ground, and dried for medicinal use. Many herbalists recommend using the leaves to brew a tea in order to benefit from hawthorn side effects. The herb can also be bought in an extract form or in capsules containing powdered leaves and berries. The recommended amount to experience hawthorn side effects is roughly 200 mg a day.
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While most holistic doctors claim there is no harm in doubling or tripling that dose, some users claim that taking too much hawthorn can induce sleepiness. Others have reported fainting spells due to extremely lowered blood pressure as one of the negative hawthorn side effects when the herb is taken in excess. The plant is not toxic, but some doctors warn it can interfere with beta-blockers and other types of medication.