The Hungry Microbiome: why resistant starch is good for you

(Narrator) We know that many
plant foods benefit our health.

Scientists now believe

one reason for this lies
with the gut Microbiome

the bacteria in your intestines.

Your microbiome is nourished
by meals like this,

rich in one type
of dietary fibre,

called resistant starch.

Resistant starch can’t be
digested by your body,

but instead becomes food
for your gut bacteria.

Most starch is easily digested.

Starch is dissolved
in the small intestine

and then absorbed by your body,

providing you with
energy and nutrients.

The remaining, non-digestible
portion is called Resistant starch.

The Resistant starch continues
its journey through your gut

and arrives at the
large Intestine.

Here, we see that the Resistant
Starch has become exposed

to the healthy bacteria
of the gut microbiome.

This species of bacteria specialize in
breaking down resistant starch.

This breakdown process
provides the bacteria

with the fuel they
need to survive.

As they use the
starch for energy,

they release small
carbohydrate molecules.

The neighbouring bacteria
feed on these carbohydrates.

As the bacteria feed,

they excrete even smaller
molecules as waste.

One of the final waste
products is called butyrate,

an energy source for your body.

As the butyrate builds up,

it is absorbed by the
large intestine.

The presence of butyrate
encourages blood to flow

into the vessels of the large
intestine, keeping the tissue healthy.

If your diet includes
enough resistant starch,

these cells will use butyrate
as their main source of energy.

Here, we can see the
molecular surface

of one of the intestinal cells.

The surface is covered
in special proteins

that actively pump butyrate
molecules into the cell.

Once inside, they can be
harvested for energy.

In addition butyrate
has other benefits.

Intestinal cells are
sensitive to DNA damage,

caused by environmental factors.

This cell’s DNA
has been damaged,

resulting in a mutation.

More damage can accumulate
over time as the cell divides,

which could lead to
colorectal cancer.

But, a steady supply of butyrate

allows the damage to be
more easily detected,

and, the cell can activate a
suicide program in response.

Because the damaged
cell destroys itself,

it can’t progress
to form a cancer.

A starved microbiome is unable
to protect you from cancer.

By eating foods rich
in resistant starch,

you can nourish your microbiome
and improve your health!

[Music plays]