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FOOD
2. Gut health
The bacterial species in our gut
are known collectively as the gut
microbiota. A diverse and abundant
gut microbiota is key to overall
health; from helping to digest
and extract nutrients from our
diet to synthesising vitamins and
neurotransmitters, maintaining
bowel motility, supporting immune
function, reducing inflammation and
guarding against harmful toxins or
pathogens. Good gut health is key to
feeling good. The good news is that
by supporting our gut microbiota we
can positively impact our systemic
health. Gut bacteria feed off soluble
fibre, also known as prebiotic fibre.
Different bacterial species ferment
different fibres, so by eating a eating
a diverse variety of plant-based
fibres we can cultivate a diverse
microbiome and all the associated
health benefits.
3. The immune system
Gut health is key to our immune
system. More than 70% of our
immune system is in our gut, where it
helps to provide a first line of defence
against foreign invaders, including
ingested bacteria, toxins and
pathogens. Our gut bacteria ferment
dietary fibre to create compounds
known as short chain fatty acids
(SCFAs). Studies show that SCFAs,
such as butyrate, have powerful antiinflammatory
actions and can help
to support the gut lining, preventing
so-called 'leaky gut' and reducing
inflammation throughout the body.
As inflammation is believed to
be at the root of all chronic disease,
its clear that supporting your gut
microbiota and production of
SCFAs by eating enough fibre is
key to lowering inflammation and
supporting overall health.
4. Blood sugar
Fibre slows the breakdown of
carbohydrates and the absorption of
sugars in to the bloodstream and can,
therefore, help maintain balanced
blood glucose levels, consistent
energy and fewer sugar cravings.
Soluble fibre dissolves in water in
the gut creating bulk and slowing
digestive transit. This helps us to feel
full and satisfied after a meal making
us less likely to snack, which may be
why higher fibre diets are associated
with better appetite control and
maintaining a healthy weight.
SCFAs, byproducts of gut bacterial
fermentation of soluble fibre, also
play a key role in blood sugar balance
through a variety of mechanisms.
SCFAs have been shown to influence
lipid and glucose metabolism and
lower inflammation, all of which are
key to improving insulin sensitivity
and lowering the risk of developing
metabolic conditions such as type 2
diabetes and obesity.
5. Mental health
Increasing dietary fibre may lower
your risk of depression. Whilst the
mechanisms are not fully understood,
we now know up to 90% of serotonin,
our 'happy hormone' is produced in
the gut and inflammation is thought
to be a key driver of depression.
Given the link between the gut
and the brain also known as 'the gut
brain axis' and recognising the role of
gut health in lowering inflammation,
it has been hypothesised that
by increasing dietary fibre and
supporting gut health, we may be
able to lower inflammation and
support neurotransmitter serotonin
production in the management
of depression.
6. Cholesterol
Fibre can positively affect our
cholesterol levels. Ideally, we should
have more of the HDL (high density
lipoprotein) than LDL (low density
lipoprotein), and fibre can help us
achieve this balance by forming a gellike
substance in the gut that binds
to LDL cholesterol, eliminating it in
the stool. Beta-glucan a fibre found
in oats and mushrooms, is especially
effective at lowering cholesterol
levels via this mechanism.
How much?
How much fibre do we need?
While the average person in the UK
currently only consumes 17g of fibre
daily, it is thought we should be
aiming for 30g of fibre per day. What's
more, as there are two different types
of fibre, with different roles and
different gut bacterial species feed
off different types of plant fibre, so
variety and diversity of fibres is key to
getting the various health benefits.
We should aim to get as many
different types of fibre in our diet
as possible in order to cultivate a
diverse microbiome and their diverse
health benefits. It's been suggested
we should aim to consume around
30 different plant foods a week. This
includes vegetables, fruit, whole
grains, pulses, legumes, nuts, seeds,
as well as herbs and spices.
The amount of fibre consumed
should be increased slowly to avoid
digestive discomfort. While fibre is
one of the most beneficial dietary
interventions for gut health, it can
take some time to adjust. It's also
important to drink the recommended
two litres (roughly eight glasses) of
water daily. Soluble fibre absorbs
water, so staying hydrated is
important to ensure stools remain
soft and easy to pass.
Some great high fibre foods
include seeds, notably chia seeds and
flaxseeds/linseeds, also oats, nuts
and nut-butters, berries, stewed
apple (skin on), wholegrain brown
rice, quinoa, beans, pulses as well
as vegetables.
Swap breakfast cereal for
overnight oats with chia seeds and
mixed berries. Or add mixed seeds
and sauerkraut to a salad at lunch.
Replace refined white wheat pasta
for red lentil pasta for an easy higher
fibre alternative.
www.mayknightnutrition.com