Healthy Eating: True or False
True or False: Avocados are the most fattening fruit?
eggs bad for your heart? Are avocados really full of fat? Can too many
carrots make you orange? And are negative calories fact or fiction? Find
out the truth behind these popular food myths.
rumor is technically true. (California) avocados are the
highest-calorie fruit in existence – packing just over 300 calories and
29 grams of fat per medium size avocado (200 grams). However, not all
fats are created equally – some are actually beneficial for you and the
majority of the fat in an avocado falls into this “good” fat category.
Only 4 grams are the unhealthy saturated kind; while the rest of the fat
content is divided between the heart-healthy monounsaturated fat (66%)
and polyunsaturated fat.
Unlike saturated and trans fats, which
raise your low-density lipoprotein (LDL) cholesterol, the good fat in
avocadoes actually lowers your (bad) LDL cholesterol while raising the
good high density-lipoprotein (HDL) cholesterol. Why is that so
important? While LDL cholesterol causes plaque to build up on arterial
walls, which causes the arteries to narrow, interfering with blood flow,
HDL cholesterol helps to remove LDL cholesterol from the blood. In
fact, high levels of LDL cholesterol and low levels of HDL cholesterol
are associated with increased risk of heart disease and stroke. The goal
is to raise the HDL, while lowering the LDL – with an optimal ratio of
LDL to HDL of 2 or 3 (definitely less than 4). Substituting harmful
saturated fats, such as butter or pastries, with healthy monounsaturated
fats, such as an avocado, is an excellent way to start.
from decreasing the risk of heart disease, monounsaturated fats also
help to reduce inflammation and to normalize blood sugar levels.
Avocadoes are also rich in many essential nutrients including fiber,
potassium, Vitamin E and many of the B Vitamins.
True or False: Eggs are bad for your heart?
Many people are afraid to eat more than 1 or 2 eggs a week, why? Because
they think that eggs will increase their cholesterol. Now it’s true
that eggs are high in dietary cholesterol – more than 200mg, which is
more than two-thirds of the American Heart Association's recommended
limit of 300 mg a day; however, dietary cholesterol and blood
cholesterol are not the same thing. Dietary cholesterol is found in food
of animal origin while blood cholesterol is a waxy substance that is
produced naturally by the liver. According to the American Heart
Association, around only 25% of the cholesterol in our body comes from
dietary sources; the rest (75%) is actually manufactured by our liver
and other cells. So does dietary cholesterol increase one’s blood
cholesterol levels? While it does increase one’s total and LDL
cholesterol, it is not as much as one would think. Other dietary factors
specifically saturated and trans fats have a much bigger impact. In
fact, studies have shown that over-consumption of both of these “bad”
fats can (and does) significantly increases one’s LDL cholesterol,
resulting in the buildup of plaque on the arterial walls, which can lead
to heart disease. A study (published in the Journal of the American Medical Association
that examined the dietary habits of 117,000 health professionals over a
14-year period found that eating one egg per day is unlikely to
increase the risk of coronary heart disease and stroke in healthy
adults. So labeling eggs as bad for the heart is essentially connecting
the wrong dots. While they may be high in dietary cholesterol, each egg
only contains 2 grams of saturated fat as well as no trans fats. What is
far worse for your heart is that buttered toast, those chocolate chip
pancakes or that cinnamon roll lying next to your eggs.
Now that it has been settled that eggs are not going to be end of your
heart, did you know that they are really good for your brain? Apart from
being rich protein, eggs are high in choline – a key component of many
fat containing structures in the cell membranes. In fact, choline is an
important part of two fat-like molecules in the brain
(phosphatidylcholine and sphingomyelin) that make up a significant
portion of the brain's mass; therefore it is critical for brain
function. It is also an integral part of the neurotransmitters which
relay messages between the nerves and muscles. Like so many other
nutrients, our bodies can only produce tiny amounts of choline, and we
must therefore rely on external sources (i.e food) – eggs are one of the
highest sources on the planet.
True or False: Some foods have negative calories?
You probably heard this one back when you were in high school – whenever
that was - as this is one myth that refuses to fade. Some people say
“negative calories” are a joke, while others swear by it. So what is the
real story here? Do some foods really decrease your caloric intake?
The theory suggests that the energy used to chew, swallow and basically
digest certain fruits and vegetables, such as celery, cucumber and
broccoli, exceeds the caloric content of the food. For example, one uses
up 80 calories digesting a serving of broccoli that contains only 25
calories; so simple math would dictate that this serving of broccoli has
negative 55 calories. While this sounds great, and most of wished it
were true, it unfortunately is really not the case. The thermic effect
of food - the amount of energy used to consume, digest and then
eliminate it - has been (scientifically) established to be far less than
supporters of this diet claim. In fact, digestion only uses up about
10% of the food’s total calories on average. So that 80 calorie cup of
broccoli still leaves you with 70, and this theory goes out the window.
True or False: Grapefruit burns fat?
Another myth that commonly circulates throughout the high school
cafeteria (and girl’s locker room) is that grapefruits burn fat.
Contrary to what you may have heard, no food itself can burn fat.
However, some foods can help you shed a few pounds – grapefruits are one
of them. Before the low carb diet, there was the grapefruit “diet”– a
fad regime that strictly limited calories and dictated that dieters
drink grapefruit juice or eat a half of a grapefruit with every meal.
While the diet isn’t particularly healthy, as it severely limits
calories to an extremely low unhealthy level, there is some truth about
eating a grapefruit with your meal. Studies have shown that the enzymes
found in grapefruits may help to regulate insulin levels, which
typically increase after one eats sugar and other carbohydrates.
Metabolic studies have shown that high levels of insulin cause more fat
to be stored, while chronically high insulin spikes can eventually lead
to insulin resistance, resulting in metabolic syndrome.
Aside from helping out your metabolism, this citrus fruit may also
reduce the risk of heart disease as they contain pectin - a form of
soluble fiber that has been shown (in studies) to slow down the
progression of atherosclerosis (build up of plaque on the arterial
walls). Red and pink grapefruits are also abundant in the
cancer-fighting anti-oxidant – lycopene; all types of grapefruits
(including white) are rich in the immune boosting Vitamin C as well as
boost the production and activity of liver detoxification enzymes that
are responsible for eliminating toxic compounds from the body – which is
also beneficial for weight loss.
True or False: Eating too many carrots can make you orange?
As strange as this one sounds, this rumor is so true. Carrots are rich
in beta-carotene, a precursor to Vitamin A. There are two sources of
dietary vitamin A: active forms and precursors. Active forms of vitamin A
are obtained from animal products such as eggs. These are known as
retinoids and include retinal and retinol. The other form is carotenoids
– photonutrients responsible for the bright colors of fruits and
vegetables. Beta-carotene is one of the 600 members of the carotenoid
family, and can be found in abundance in carrots, sweet potatoes and
pumpkins - basically any fruit or veggie with a yellow orange color.
Once consumed, beta-carotene can be converted into Vitamin A, as needed
by the body.
As an anti-oxidant, beta-carotene rids the body of harmful free radicals
that can cause aging, cardiovascular diseases and even cancer. It also
helps to boost the immune system, helps the reproductive system function
properly, is vital for our eyes as it protects them for light-induced
damage and of course is a source of vitamin A. However, unlike the
active form of vitamin A, which can cause toxic effects if taken in
large doses, beta-carotene will only convert itself into the vitamin if
needed. It is stored in the liver until then. Nonetheless, overeating
beta-carotene rich foods, such as carrots, can result in excess carotene
in the blood, resulting in yellowing of the skin most often on the
palms and bottom of the feet. This condition is referred to as
carotenodermia and is harmless; it can easily be reversed.