Lipids are not sexy.  They do not give anyone erotic stirrings, they do not start revolutions or catch criminals.  However, without them, life as we know it would simply not exist.  Let me explain.

Cells are well known as the smallest units of life.  Their discovery in London in the 17th century by Robert Hooke raised, and continues to raise, a bewildering array of questions:  ‘What makes them alive?’ ‘What molecules are cells made of?’

We now understand that there are only about three types of large molecule that make up the physical blocks of life.  Nobel Prizes have been won for work on two of these, namely, DNA [1] and proteins [2].  The understanding that work on DNA and proteins has given us has led to other questions.  For example, not only has the structure of DNA been discovered but its’ purpose is now also understood.

The link between these first two classes of molecule is that the DNA codes for the proteins.  DNA is divided up into genes, and one gene codes for one protein.  Proteins are the machinery that allow cells to work.  With proteins, cells can exert control on the chemical processes that are essential to survival.  But what about the bits in-between the proteins in a cell?  What about the bricks and mortar that hold the cell together?  It is a good question.  This is the job of the third class of large molecule that makes cells what they are: lipids.

Windows, doors, tables, chairs, bookcases and novelty vacuum cleaners all tell you a lot about a house.  But, like the proteins of a cell, they need something to hold them together in order to make them a house and not just the contents of a skip.  In building a cell, that job falls to lipids and therefore the analogy with the brick is not as distant as it might sound, either metaphorically or practically.

Lipids come as many varieties, though they are rarely unique.  Individual parts are never a focus when looking at the whole construct, but of course we notice when they are not there.  And when they are there they do not seem to do much.  But they have a physical job: crudely, they fill up the space in between the more interesting bits and hold them in place.  This is perhaps why they have not received as much scientific or media attention as other components of the cell.  This is why they are not ‘sexy’.  In any case, they are better than that.  They are useful.


[1] F. H. C. Crick, J. D. Watson, M. H. F. Wilkins, Nobel Prize for Physiology, 1962.

[2] L. H. Hartwell, T. Hunt, P. M. Nurse, Nobel Prize for Physiology, 2001.