3.24.2008

Sage improves memory and attention

'He that would live for aye,
Must eat Sage in May.'
The old English proverb, quoted by venerable herbalists from Gerard to Maude Grieve, refers to the virtues of the common garden sage (Salvia officinalis). This gracious aromatic herb, of a dry and warming energy, was long considered to confer immortality, a quickness of wit and eye, and protection from disease.
Previous research has shown evidence for sage's ability to enhance mood, reduce anxiety, and improve performance in healthy young volunteers (lemon balm, too), and the in-vitro research on the herb's ability to exert anti-cholinesterase activity (prolonging the activity of the neurotransmitter acetylcholine) has made it a target for research in aging and dementia. Acetylcholine is involved in transmitting signal in an area of the brain called the basal forebrain (amongst others), and there is evidence that this region of the central nervous system degrades as we age, leading to memory loss and cognitive impairment (as in Alzheimer's, for instance). Acetylcholine also provides the connection between the nervous system and musculature, and deficiencies are associated with conditions such as myasthenia gravis.
In this most recent study, 20 healthy older volunteers aged 65 to 90 were given various doses of a sage extract, and the results indicate an improvement in a variety of cognitive markers, along with a reduction in the score dropoff over the course of the day (the volunteers stayed sharper, longer). Some details:
  • the extract was made with 70% alcohol, then concentrated and freeze-dried to a final weight-to-volume ratio of 7.5:1. This is pretty darn concentrated. Researchers were going for the volatile terpenes primarily (well-soluble in alcohol). They found 333mg to be the most effective dose; this is about 2.5 grams of leaf, or about 7.5 ml (1 and 1/2 tsp.) of a 1:3 tincture of sage.
  • the extract was compared to placebo, in a variety of categories including word recognition and recall; vigilance; reaction time; spatial and numeric memory; and delayed picture recognition tests. Below are graphs of the changes in (a)secondary memory and (b)accuracy of attention:









So, sage is definitely worth considering in the context of other herbs such as Ginkgo and Rhodiola in helping buffer the effects of aging on otherwise healthy minds. Perhaps there is indeed some wisdom in the old Latin proverb, Cur moriatur homo cui Salvia crescit in horto? ('Why should a man die as long as sage grows in his garden?'). Or at least, why should he (or she) grow old and forgetful?

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