Vitamins, minerals, probiotics and other general and sport health aids and supplements, diagnostic and medical care equipment and consumables, glasses, medical and DNA testing, medicines, sexual health and everything you would find in a pharmacy.
Prescription glasses from £10, branded glasses from £19.95, also designer, bifocals and sunglasses. UK delivery £2.50. Worldwide delivery also possible.
A huge range of health and beauty. Also toys and mother & baby. Delivery on most orders free over £40, otherwise £4.84 to home or £2.89 to a store.
Discounted prescription glasses including designer styles and sunglasses. Single vision and complex prescriptions.
Up to 30% discount on contact lenses delivered free to your home or workplace. Also lens essentials such as cleaning solutions and sunglasses 
Prescription classic, safety and designer glasses and accessories. Sizing guide and catalogue available. Try up to 4 pairs at home. UK delivery £3.75, free on 2 pairs. 
Health supplements and aids, such as Megavent to help stop snoring. Also lots of information and recipes. First class UK delivery £2.50 per order.
Vitamins, skincare food supplements, similar products for animals and related books. Free UK and EU delivery 
Vitamins, minerals and supplements. Frequent large discounts. Online guides to nutrition and fitness. Delivery £1.99 to mainland UK.
Branded contact lenses delivered rapidly at substantial discounts on optician prices. Also solutions and other accessories. Standard UK delivery £2.99
Major pharmacy with over 1700 shops. Toiletries, healthcare and medication. Free UK p&p over £40, otherwise £3.95
Supplements that are as close as possible to natural foods. Free UK delivery over £25, otherwise £1.95 per order. 
Thin lenses, designer brands, single and complex vision, designer frames, all at discounted prices with special deals every day.
Health & beauty products with an emphasis on health, including medicines. Free delivery to the UK over £45, otherwise £2.95 per order.
Officially registered in UK (Jersey) as a pharmacy selling everything normally found at a High Street chemist. UK delivery free over £45, otherwise £2.95 per order.
Electric shavers for men and women, also healthcare, toothbrushes and small household electricals. Free standard UK delivery on everything 
Health products, cosmetics gifts, often at seriously reduced prices. Standard UK delivery free on orders over £35 otherwise £3.
Food intolerance finger prick blood test. Find out which food is making you ill. Also other allergy and body wellness tests.
Holland & Barrett are best known from their TV adverts and High Street shops for vitamins, essential minerals and food supplements, but they also offer information on the web site. There is a complete vitamin guide, advice related to specific health conditions and to nutrition-related sport and fitness. They deliver worldwide, but their charges for posting abroad a quite high. UK mainland delivery is £1.99.
Nature's Own also concentrate on vitamins and natural supplements. They try to avoid artificial compounds, instead blending ingredients that are 'as close as possible to natural foods'. They charge £1.95 for UK delivery if your order is under £25, otherwise it is free. Higher Nature also sell vitamins and supplements, but, unusually, have similar products for animals too, and everything is delivered free.
Pharmacy2u can supply medications. Both sell creams, ointments and other similar preparations for health care and improvement.
The online glasses (spectacle) suppliers make and deliver glasses to your prescription. They have lower overheads than the traditional High Street opticians and they pass the savings on to customers. Glasses are available from £15, including lenses, sometimes even less. Designer, rimless, bendable, safety and several other kinds of glasses are available, as well as cleaning materials, cases etc. They provide a sizing and fitting guide and a money-back guarantee. Glasses Direct also have a catalogue. Alternatively, you can see ranges from them, from Perfect Glasses, Best4Glasses and from Exclusive Eyes online. Glasses Direct even have a system that lets you upload a photo of yourself and see how the glasses would look on you or you can try up to four pairs at home. It is worth looking at all three suppliers because they have offers that change frequently, such as free anti-glare and scratch-resistant coatings.
Yorktest have kits that enable you to test for food intolerance, other allergies, liver function etc. They also have books on food and health issues.