Nutmegs are the seeds of the nutmeg tree. The red lacy covering of the seeds is the rather spicier spice, mace.

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You can buy ready ground nutmeg or whole nutmegs to grate as needed. They even sell special miniature nutmeg graters which are really cute even though any normal, fine grater works or a sharp knife. Whole nutmegs last much longer than ready ground. Like all herbs and spices, keep it somewhere dry and dark, away from extremes of temperature.
Nutmeg is rich in antioxidants, is anti-inflammatory and antibacterial hence sometimes used in dental products.
It has vitamins C, A and E, plus minerals manganese, magnesium, iron, phosphorous, potassium, copper and zinc.
Most famously it helps with sleep (you can put a few drops of aromatherapy oil on your pillow) and has some mood enhancing effects.

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Nutmeg helps avoid blood-sugar spikes although is unlikely to cancel out the effects of childhood favourites; as topping on rice pudding, egg-custard tarts or in Christmas day apple sauce.
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All these benefit from the addition of nutmeg’s wonderfully warming taste as do hot chocolate, coffee and mulled wine.
Like many good foods, more is not better. This is one to use in moderation as large amounts are toxic so keep it to less than a teaspoon a day.
Bechamel sauce is used in lasagna; the nutmeg and bay give its distinctive fragrance.
Put a bay-leaf into 600ml (1 pint) of milk to infuse. Heat gradually until hot but not boiling. Remove the bay-leaf.
Melt 40g (1½ oz) of butter in another pan.
Add 40g (1½ oz) of plain flour and cook stirring for a minute.
Take off the heat and gradually add the milk, stirring all the time. Return to the heat and simmer for 3 minutes until thickened.
Season with salt, pepper and nutmeg.