Astragalus and Frequent Colds: The Traditional Reasoning, Plus the Evidence

If you have read about frequent colds and Chinese medicine, Astragalus was probably in the list. This article narrows it down: why the tradition uses it here, what evidence exists, and how to actually take it.

In pattern terms, this is about lung qi deficiency with a weak voice and short breath. Astragalus (Huang Qi, 黄芪) is slightly warm in nature and enters the spleen, lung meridians, which is the classical reason it suits that picture.

Classically, it tonifies wei qi, the defensive energy that keeps colds away. A practitioner matching your tongue and pulse to that pattern is exactly the situation it was chosen for.

The evidence for Astragalus

Clinical work has focused here: recent scientific reviews have evaluated the research on astragalus for various conditions. A 2024 review of 20 studies (involving 953 adults with type 2 diabetes) found that taking astragalus in addition to the medicine metformin reduced fasting blood glucose and hemoglobin A1C more than metformin alone. (HbA1C measures the average blood glucose over the prior few months.) Most of the studies, however, were of low quality and found to have bias.

How people take it for frequent colds

Simmer 9 to 30 grams of sliced root long, an hour or more, in soups; remove the slices before serving. A thermos of astragalus tea through flu season is a common household habit in China.

Acupressure runs alongside the herbs in most treatment plans. The points most often paired with this pattern are zusanli, fengmen, and pressing them firmly for a minute at a time is easy to learn.

For the fuller picture, including the other patterns behind frequent colds, see the Getting Sick Often guide.

Cautions

A few cautions from the research literature: little is known about whether it’s safe to use astragalus during pregnancy or while breastfeeding.

Consistency beats dose. A modest amount taken regularly usually does more than a heroic amount taken twice.