People today may be surprised to learn that until early in the 20th
century, chocolate was considered to be a health food, with a range of
potential health benefits. It was used thousands of years ago by the
ancient Mayans and Aztecs, and much later by Europeans between the 16th
and 19th centuries, as an ingredient in cures for many illnesses,
including fevers, liver disease, and kidney disorders, dysentery, and
constipation, and to foster needed weight gain. Perhaps underlying its
current role on St. Valentine’s day, the original chocolate drink was
used by the Aztecs as an aphrodisiac, and some European doctors in the
1700 and 1800’s said chocolate made people amiable and "incited consumers to... lovemaking."
As discussed in What’s New? there is some scientific
evidence that a little bit of chocolate each day may do you good. But
all chocolates were not created equal...
Chocolate nutrition
It
is relatively simple to compare your favourite kind of chocolate by
looking at the Nutrition Facts / Information Panel which is found on
most foods. The table lists the nutrient composition of the more common
varieties in a 10 g (1/3 Ounce) serve, which is equivalent to 2
squares/pieces of an average bar/block.
As can be seen, all chocolates are relatively high in
kilojoules/Calories, mainly because of their fat content. Most are also a
good source of carbohydrates, mainly because of added sugars that help
mask chocolates naturally bitter flavour. The exception is the
stevia-based chocolate bars which use sugar alcohols and inulin instead
of added sugars to provide bulk and texture.
Body weight
Most
chocolates are what we call energy dense – you get a lot of
kilojoules/Calories in a relatively small volume. This is good if you
are trying to gain wait, travel long-distances with limited storage
space, or participate in an endurance sport where it is an advantage to
be able to carry around a concentrated and highly palatable source of
fat, carbohydrate and energy. But it is obviously not good if you are
trying to lose weight.
Blood fats
Chocolate
is high in total and saturated fats. In high quality chocolates, cocoa
butter is the main source of fat. This is important, because cocoa
butter is high in a particular kind of saturated fat called stearic
acid. Stearic acid raises the “bad” LDL cholesterol the least of the
saturated fats but does not lower the “good” HDL cholesterol, so the net
effect on your total blood cholesterol levels is not so bad. However,
the amount of cocoa butter used in chocolate does vary, and along with
it the amount of the stearic acid, but this information is usually not
provided in any simple form on the chocolate wrapper. As a rough guide,
the better quality, and as a result, more expensive varieties generally
have more cocoa butter, and as such are usually a better choice.
Blood glucose
Despite
most chocolates relatively high carbohydrate (primarily added sugars)
content, they don’t have as large an impact on blood glucose levels as
some imagine - unless you overindulge, of course. This is because all
contain around 5 g of carbohydrate per 10 g serve (with the exception of
the new stevia based chocolate bars which have less than 1 g per
serve). Also, the glycemic index of chocolate is low with values less
than 45 for most common varieties (see Your GI shopping guide, below).
This is because of the high fat content, which slows the rate that the
sugars are released from the stomach into the small intestine, and
absorbed into the blood. So overall, the glycemic load is less than 10
(low) for a typical serve of most common varieties.
For
this reason, as long as they don’t overindulge, people with diabetes do
not have to eat low, or reduced-sugar chocolates to avoid high blood
glucose levels. It’s important to note that while the low carbohydrate
stevia varieties will have the least effect on blood glucose levels they
are relatively high in fat and consequently have nearly the same amount
of kilojoules as regular varieties so they are not much better if you
are trying to lose weight. Also, alternatively sweetened chocolate is
usually more expensive and often not as tasty as sugar-sweetened
chocolate.
There is a good argument that you should have a little bit of what you enjoy…as a colleague once said “If you really like chocolate and don’t wish to over consume the product, always choose your favourite!”
Antioxidants
As
discussed in What’s New? chocolate is one of natures richest sources of
a powerful group of antioxidants known as flavanols, along with green
and black tea, red wine, certain fruits (e.g. berries, black grapes,
plums, apples) and vegetables (e.g. artichoke, asparagus, cabbage,
russet and sweet potatoes). These antioxidants are thought to possess a
number of properties that may benefit health, including helping to
prevent cholesterol sticking to the walls of blood vessels, relaxing
major blood vessels and thereby decreasing blood pressure, and maybe
even reducing the ability of the blood to form too many clots. Half a
row of dark chocolate (25 g / 0.9 Ounces) provides about the same amount
of these antioxidants as half a cup of black tea or a glass of red
wine. It’s important to remember that milk chocolate contains only one
third as much antioxidants as dark chocolate, and white chocolate
contains none at all.
Bottom line
While
not a health food, if eaten in moderation, most people can enjoy
chocolate as part of a well-balanced diet. Dark chocolate may have some
cardio-vascular benefits. Those who are overweight should only buy
their favourite, high quality chocolate, and take care not to eat too
much, too often.
Read more:
- Cardiovascular disease risk of dietary stearic acid compared with trans, other saturated, and unsaturated fatty acids: a systematic review
- Effects of stearic acid on plasma lipid and lipoproteins in humans
Alan Barclay, PhD is a consultant dietitian and chef (Cert III). He worked for Diabetes Australia (NSW) from 1998–2014 . He is author/co-author of more than 30 scientific publications, and author/co-author of The good Carbs Cookbook (Murdoch Books), Reversing Diabetes (Murdoch Books), The Low GI Diet: Managing Type 2 Diabetes (Hachette Australia) and The Ultimate Guide to Sugars and Sweeteners (The Experiment, New York).
Contact: You can follow him on Twitter or check out his website.
