Lemons are a type of
citrus fruit that derive from the flowering plant Rutaceae. Lemon water is
simply the juice from lemons mixed with water.
Lemons are high in
vitamin C, fiber and various beneficial plant compounds. Here are the health
benefits of lemons:
1. Support heart health
Lemons are a good source
of vitamin C. One peeled lemon provides about 53 mg of vitamin C, which is
almost 60% of the reference daily intake (RDI).
Vitamin C reduces the
risk of heart disease and stroke. In addition, the fiber compounds in the pith
(white exterior) of lemons could also lower some risk factors for heart
disease.
A review of 14 studies found
that an average increase of 10 mg of flavonoids (which found in lemons and
lemon peels and have antioxidant properties) per day reduced heart disease risk
by 5%.
2. Help manage weight
Lemons are often
promoted as a weight loss food. The soluble pectin fiber in them expands in the
stomach, which may help you feel full for longer.
But because lemon juice (or
lemon water) contains no pectin, lemon juice drinks will not promote fullness
in the same way.
3. Prevent kidney stones
Citric acid may help
prevent kidney stones by increasing urine volume and increasing urine pH,
creating a less favorable environment for kidney stone formation.
Just a half cup (4
ounces or 125 ml) of lemon juice daily may provide enough citric acid to help
prevent stone formation in people who have already had them.
However, more
well-conducted studies are needed to confirm whether lemon juice affects kidney
stone formation.
4. Protect against
anemia
Lemons contain some
iron. But they primarily prevent anemia by improving the absorption of iron
from plant foods as iron from plant sources (non-heme iron) does not absorb as
easily. This absorption can be improved by consuming vitamin C and citric acid.
5. Reduce cancer risk
As a matter of fact, a
healthy diet rich in fruits and vegetables can help prevent some cancers.
What is more, it was
found that flavonoid intake is associated with a reduced risk of several types
of cancer. And vitamin C may bolster the
growth of white blood cells, which help eliminate mutated cancer cells.
In addition, lemon peel (see
below) may also have several cancer-fighting properties. Lemon peels are an
excellent source of terpenes such as D-limonene (a compound that gives lemon
its characteristic aroma). The primary health benefits of terpenes revolve
around some impressive anticancer effects – both in prevention and possibly
treatment. Specifically, D-limonene reduced the expression of breast tumor
cyclin D1 (cyclin D1 is one of the frequently overexpressed proteins and one of
the commonly amplified genes in breast cancer).
One test-tube study also
found that D-limonene helped kill stomach cancer cells. Similarly, a 52-week
study in rats noted that different concentrations of D-limonene inhibited
stomach cancer by increasing the death rate of the mutated cells.
Nevertheless, lemon peel
should not be considered a treatment or cure for cancer. Human research is
needed.
6. Improve digestive
health
Lemons contain about 10%
carbohydrates, mostly soluble fiber and simple sugars. The main fiber in lemons
is pectin, a form of soluble fiber.
Soluble fiber can
improve gut health and slow the digestion of sugars and starches. These effects
may result in reduced blood sugar levels.
However, to get the
benefits of fiber from lemons, you need to eat the pulp. People who drink lemon
juice without the pulp will miss out on the benefits of fiber.
Lemon peel
While the pulp and juice
are used the most, the peel tends to be discarded. However, studies have
determined that lemon peel is full of bioactive compounds that may provide
numerous health benefits.
Besides fighting cancer as mentioned above, research shows that lemon peel also has many other health
benefits because of its fiber, vitamin and antioxidants.
Lemon peel packs a high
amount of fiber and vitamin C, providing 9% of the DV in only 1 tablespoon (6
grams). It also has small amounts of calcium, potassium and magnesium.
Additionally, it has other health benefits as well:
1. May support oral
health
Dental cavities and gum
infections are widespread oral diseases caused by bacteria like Streptococcus
mutans. In one study, researchers identified four compounds in lemon peel that
have powerful antibacterial properties and effectively fight common
oral-disease-causing bacteria.
2. High in antioxidants
Lemon peel is high in
antioxidants, including D-limonene and vitamin C.
Intake of flavonoid antioxidants
like D-limonene is linked to a reduced risk of certain conditions, such as
heart disease and type 2 diabetes.
Animal studies also show
that D-limonene increases the activity of an enzyme that helps reduce oxidative
stress. Oxidative stress is associated with tissue damage and accelerated
aging.
Additionally, the
vitamin C in lemon peel acts as a powerful antioxidant and likewise promotes
immune health.
A review of 82 studies
found that 1–2 grams of vitamin C per day reduces the severity and duration of
the common cold by 8% in adults and 14% in children.
Vitamin C also
accumulates in phagocytes, a type of cell that ingests harmful compounds.
3. Have
antimicrobial and antifungal properties
In a test-tube study, it
was found lemon peel significantly harmed and reduced the growth of
antibiotic-resistant bacteria.
Another test-tube study
showed that lemon peel extract fought a drug-resistant fungus that causes skin
infections.
Despite these promising
findings, human studies are needed.
4. May promote heart
health
In a study in mice with
obesity, D-limonene lowered blood sugar, triglyceride and LDL (bad) cholesterol
levels, while increasing HDL (good) cholesterol.
A 4-week study in 60
children with excess weight noted that supplementing with lemon powder
(containing peel) led to reductions in blood pressure and LDL cholesterol.
The pectin in lemon
peels may also reduce cholesterol levels by increasing the excretion of bile
acids, which are produced by the liver and bind to cholesterol.
5. May treat gallstones
Some studies suggest
that D-limonene may help treat gallstones — hard deposits that can develop in the
gallbladder.
In a study in 200 people
with gallstones, 48% of those injected with a D-limonene solvent experienced
complete gallstone disappearance, suggesting that this treatment could be an
effective alternative to surgery.
But more studies are
needed.
