food can improve its taste, but it also changes the
Interestingly, some vitamins are lost when food is cooked,
while others become more available for your body to use.
Some claim that eating primarily raw foods is the path to
better health. However, certain cooked foods have clear
This article discusses the benefits of both raw and cooked
What Is a Raw Food Diet?
Raw foods are foods that have not been cooked or processed.
While there are various types of raw food
diets, all of them involve eating mostly unheated, uncooked
and unprocessed foods. In general, a raw food diet is made up
of at least 70% raw foods.
The diet often includes fermented foods, sprouted grains, nuts
and seeds, in addition to raw fruits and vegetables.
Many raw foodists consume a vegetarian or vegan
diet, eliminating animal products and eating mostly raw
plant foods. However, a small number also consume raw dairy
products, fish and even raw meat.
Advocates claim that raw foods are more nutritious than cooked
foods because enzymes, along with some nutrients, are destroyed
in the cooking process. Some believe that cooked food is
While there are some clear benefits to eating raw fruits and
vegetables, there are also some potential problems with a raw
A strict raw food diet is very difficult to follow, and the
number of people that stick to a completely raw diet in the
long term is very small.
Furthermore, some foods contain dangerous bacteria and
microorganisms that are only eliminated by cooking. Eating a
completely raw diet that includes fish and meat comes with a
risk of developing a food-borne illness.
Summary: Raw food diets involve eating
mostly raw fruits and vegetables. Eating raw foods has some
benefits, but there are also potential problems.
Cooking May Destroy Enzymes in Food
When you consume a food, digestive enzymes in your body help
break it down into molecules that can be absorbed (1).
Fresh foods also contain a variety of enzymes and some people
believe they may aid your digestion.
This is one of the primary arguments in favor of raw food
diets. Some people believe that when a food’s enzymes are
altered during the cooking process, more enzymes are required
from your body to digest it.
Proponents of raw food diets claim that this puts stress on
your body and can lead to enzyme deficiency. However, there are
no scientific studies to support this claim.
In fact, plant and animal enzymes play an important role in
their metabolism, but do not help humans digest them.
Furthermore, the human body produces the enzymes necessary to
digest food. And the body absorbs and re-secretes some enzymes,
making it unlikely that digesting food will lead to an enzyme
deficiency (4, 5).
Moreover, science has not yet demonstrated any adverse health
effects of eating cooked foods with denatured enzymes.
Summary: Cooking foods deactivates the
enzymes found in them. However, there is no evidence that
food enzymes contribute to better health.
Some Water-Soluble Vitamins Are Lost in the Cooking Process
Raw foods may be richer in certain nutrients than cooked foods.
Some nutrients are easily deactivated or can leach out of food
during the cooking process. Water-soluble vitamins, such as
vitamin C and the B vitamins, are particularly susceptible
to being lost during cooking (6, 7, 8, 9, 10).
Some minerals and vitamin A are also lost during cooking,
although to a lesser extent. Fat-soluble vitamins D, E and K
are mostly unaffected by cooking.
Boiling results in the greatest loss of nutrients, while other
methods more effectively preserve the nutrient content of
Lastly, the length of time that a food is exposed to heat
affects its nutrient content. The longer a food is cooked, the
greater the loss of nutrients (9).
Summary: Some nutrients, particularly
water-soluble vitamins, are lost during the cooking process.
Raw fruits and vegetables may contain more nutrients like
vitamin C and B vitamins.
Cooked Food May Be Easier to Chew and Digest
Chewing is an important first step in the digestive process.
The act of chewing breaks down large pieces of food into small
particles that can be digested.
Improperly chewed food is much more difficult for the body to
digest and can lead to gas and bloating. Additionally, it
requires significantly more energy and effort to properly chew
raw foods than cooked ones (16).
The process of cooking food breaks down some of its fibers and
plant cell walls, making it easier for the body to digest and
absorb the nutrients (17).
Cooking also generally improves the taste and aroma of food,
which makes it much more enjoyable to eat.
Although the number of raw foodists who consume raw meat is
small, meat is easier to chew and digest when it’s cooked
Properly cooking grains and legumes
not only improves their digestibility, but it also reduces the
number of anti-nutrients they contain. Anti-nutrients are
compounds that inhibit the body’s ability to absorb nutrients
in plant foods.
Put simply, some cooked foods may provide the body with more
nutrients than their raw counterparts because they are easier
to chew and digest.
Summary: Cooked foods are easier to chew and
digest than raw foods. Proper digestion is necessary to
absorb a food’s nutrients.
Cooking Increases the Antioxidant Capacity of Some Vegetables
Beta-carotene is a powerful antioxidant that the
body converts into vitamin A.
A diet rich in beta-carotene has been associated with a reduced
risk of heart disease (21).
The antioxidant lycopene is also more easily absorbed by your
body when you get it from cooked foods instead of raw foods
One study found that cooking tomatoes reduced their vitamin C
content by 29%, while their lycopene content more than doubled
within 30 minutes of cooking. Also, the total antioxidant
capacity of the tomatoes increased by over 60% (22).
Another study found that cooking increases the antioxidant
capacity and content of plant compounds found in carrots,
broccoli and zucchini (25).
Antioxidants are important because they protect the body from
harmful molecules called free radicals. A diet rich in
antioxidants is associated with a lower risk of chronic disease
Summary: Cooking your vegetables may make
certain antioxidants more available to your body than they
are in raw foods.
Cooking Kills off Harmful Bacteria and Microorganisms
It’s better to eat certain foods cooked, as raw versions may
contain harmful bacteria. Cooking food effectively kills
bacteria that may cause food-borne illness (27).
fruits and vegetables are generally safe to consume raw, as
long as they have not been contaminated.
Spinach, lettuce, tomatoes and raw sprouts are some of the
fruits and vegetables most frequently contaminated by bacteria
E. coli, Salmonella, Listeria and
Campylobacter are some of the most common bacteria
that may be found in raw foods (30).
Most bacteria cannot survive at temperatures over 140°F (60°C).
This means that cooking effectively kills bacteria and reduces
the risk of food-borne illness (31).
Commercially produced milk is pasteurized, which means it has
been heated to kill any harmful bacteria it may contain
Summary: Cooking food effectively kills
bacteria that may cause food-borne illnesses. This applies
especially to meat, eggs and dairy.
It May Depend on the Food
Neither a completely raw nor completely cooked diet can be
justified by science.
That’s because both raw and cooked fruits and vegetables have
various health benefits, including a lower risk of chronic
The truth is that whether food should be consumed raw or cooked
may depend on the food.
Here are a few examples of foods that are either healthier raw
or healthier cooked:
Foods That Are Healthier Raw
Broccoli: Raw broccoli contains three times
the amount of sulforaphane, a cancer-fighting plant compound,
than cooked broccoli does (34, 35).
Cabbage: Cooking cabbage destroys the enzyme
myrosinase, which plays a role in cancer prevention. If you
choose to cook cabbage, do so for short periods (36).
Onions: Raw onion is an anti-platelet agent,
which contributes to heart disease prevention. Cooking onions
reduces this beneficial effect (37, 38).
Garlic: Sulfur compounds found in raw
garlic have anti-cancer properties. Cooking garlic
destroys these sulfur compounds (39).
Foods That Are Healthier Cooked
Asparagus: Cooking asparagus breaks down its
fibrous cell walls, making folate
and vitamins A, C and E more available to be absorbed.
Mushrooms: Cooking mushrooms helps degrade
agaritine, a potential carcinogen found in some
mushrooms. Cooking also helps release ergothioneine, a powerful mushroom antioxidant
Spinach: Nutrients like iron, magnesium,
calcium and zinc are more available for absorption when
spinach is cooked.
Tomatoes: Cooking greatly increases the
availability of lycopene in tomatoes (22).
Carrots: Cooked carrots provide more
beta-carotene than raw carrots (19).
Potatoes: The starch in potatoes is nearly
indigestible until a potato is cooked.
Legumes: Raw or undercooked legumes contain
antinutrients called lectins. Lectins are eliminated with
proper soaking and cooking.
Meat, fish and poultry: Raw meat, fish and
poultry may contain bacteria and parasites that can cause
food-borne illnesses. Cooking these foods kills harmful
Summary: Some foods are better to eat raw,
and some are healthier when cooked. Eat a combination of
cooked and raw foods for maximum health benefits.
The Bottom Line
Some foods are more nutritious when eaten raw, while others are
more nutritious after being cooked.
However, it’s unnecessary to follow a completely raw diet for
For the most health benefits, eat a variety of nutritious raw
and cooked foods.