Juicing seems to be a controversial subject.
Advocates say that lots of fruit and vegetable juices
represent one of the simplest, fastest and most enjoyable
routes to good health.
Critics claim that juicing is the first step on the road to
processed food - and that it degrades the produce, gives
a more rapid sugar hit - and removes valuable components of
the original produce.
This essay is an opinion piece - which gives the author's
answer to the question of if and when you should juice
Juicing is very often inferior, in many ways, to consuming
- ...leaves fat-soluble compounds bound up with the fibre;
- ...systematically filters out valuable nutrients near the skin;
- ...stops the tongue from detecting rotten, mouldy or parasitised produce;
- ...results in atrophy of the teeth and jaws;
- ...bypasses saliva - the first stage in digestion - and the first line of defense;
- ...eliminates valuable fibre from produce - resulting in:
- ...increased glycemic index;
- ...more rapid absorbsion of sugar;
- ...a sharper insulin spike;
- ...reduced satieity;
- ...slower passage through the digestive tract;
- ...easier absorbsion of excessive doses;
- ...blood sugar swings;
- ...lack of benefit of fibre to the colon;
However juicing does have some virtues:
- Eating more fruit and vegetables
While it is widely agreed that eating more fruit and vegetables is
generally a good idea, many find vegetables have palatability
problems, and that there is a limit to the volume of celery they
can be bothered to munch through.
By improving the palatability of many vegetables, juicing can
result in the consumption of produce which would not be easy or
convenient to ingest whole.
As a result, use of a juicer can increase fruit and
Increased consumption of fruit and vegetable material can
displace other less-desirable items from the diet.
- Allowing access to high-quality nutrient sources
The nutrients in some produce are protected against being eaten by
the volume of indigestible fibre they come with.
Cereal grasses - by most accounts - represent high quality nutritional
sources. However the nutrients are practically inaccessible through
being bound up with lots of fibre.
Juicers can liberate the nutrients from the fibre, and allow
convenient access to these fine foodstuffs.
- Fibre can trap foodstuffs in between the teeth
Dental carries can be caused by fibres in fruit becoming stuck
between the teeth - and holding bacterial food sources next to
By contrast, juice tends not to get stuck between the teeth.
Indeed, exposure of the teeth, tongue - and the entire mouth -
can be minimised - if the juice is consumed using a straw.
The impact of juice on blood sugar spikes can be reduced
by diluting it with water - or by using a coarse screen
that fails to filter out much fibre.
Examining some of the drawbacks of juicing suggests that
separating the skin from the sugary pulp of some fruits may
have some utility - if the fibrous pulp is eaten and the
juice is discarded.
This gives access to the nutrients in the skin - without
the burden of all the calories and carbohydrates in the
Grapes are an interesting fruit to try this trick with.
However, this may result in undesirable concentrations of
pesticides from the skins if some caution is not taken.
Juicing has numerous drawbacks - and it is good to be aware of them.
However a good juicer remains one of the most important
pieces of food processing equipment for those interested in
eating largely-raw diets.
Studies on the effects of blending, chewing and juicing
- Depletion and disruption of dietary fibre. Effects on satiety, plasma-glucose, and serum-insulin (juicing and disruption)
- The role of dietary fiber in satiety, glucose, and insulin: studies with fruit and fruit juice (juicing)
- Effects of one week juice fasting on lipid metabolism: a cohort study in healthy subjects (juicing and fasting)
- Swallowing food without chewing; a simple way to reduce postprandial glycaemia (disruption)
- Gastric emptying of a solid meal is accelerated by the removal of dietary fibre naturally present in food (juicing)
- Effects of food texture change on metabolic parameters: short- and long-term feeding patterns and body weight (satieity)
- Distribution of multiple pesticide residues in apple segments after home processing (pesticides)
- Behavioral, plasma, and calorimetric changes related to food texture modification in men (blending)
- The physical state of a meal affects hormone release and postprandial thermogenesis (blending)
- Physical state of meal affects gastric emptying, cholecystokinin release and satiety (blending)
- Lycopene in tomatoes: chemical and physical properties affected by food processing (blending)
- Food processing and lipid oxidation (disruption)
- Changes in carotenoids during processing and storage of foods (oxidation)
- A nursing home outbreak of Clostridium perfringens associated with pureed food (blending)