Fish oils come from fatty fish, also known as oily fish, specifically the tissue of fatty fish, such as trout, mackerel, tuna, herring, sardines, and salmon.

Fish oils are of interest to nutritionists and health care professionals because of two main ingredients: DHA (docosahexaenoic acid), and EPA (eicosapentaenoic acid) - both types of Omega-3 fatty acids.

The fillets of oily fish contain up to 30% oil; this figure may vary. White fish, on the other hand, only contain high concentrations of oil in the liver, and have much less oil. Apart from omega-3 fatty acids, oily fish are also good sources of vitamins A and D. Whitefish also contain these nutrients, but at much lower concentrations.

Health experts commonly tell people that oily fish have more health benefits than white fish. However, their recommendations have never been compellingly proven scientifically in large population studies.

Many health authorities around the world advise people to consume either plenty of oily fish or to take supplements, because of their supposed health benefits. Studies over the last ten years have produced mixed results regarding the benefits of the dietary intake of fish oils.
Possible health benefits of fish oils

Over the last ten years, there have been dozens of studies on fish oils and omega-3 oils. Some have backed up these claims, while others have not.

Fish oils are said to have several health benefits if they are included in a human diet, including:
Multiple sclerosis (MS)

Fish oils are said to help people with MS. However, a study carried out by researchers from University Hospital in Bergen, Norway, in April 2012 found that omega-3 fatty acids do not help people with MS.1
Prostate cancer

Fish oils reduce men's risk of developing prostate cancer if they follow a low-fat diet, one study found, while another linked omega-3 levels to a higher risk of aggressive prostate cancer2.

A study published in the Journal of the National Cancer Institute found that omega fish oils raise prostate cancer risk. The authors, from the Fred Hutchinson Cancer Research Center reported that high fish oil intake raises the risk of high-grade prostate cancer by 71% and all prostate cancers by 43%.3
Post-natal (post-partum) depression

Fish oils protect from post-partum depression - Dr. Michelle Price Judge, of the University of Connecticut School of Nursing, said after carrying out a study in 2011 "DHA consumption during pregnancy at levels that are reasonably attained from foods has the potential to decrease symptoms of postpartum depression."4
Mental health benefits

fish oils help young people with behavioral problems, especially those with ADHD.5
Memory benefits

Working memory can improve in healthy young adults if they increase their Omega-3 fatty acids intake, researchers reported in the journal PLOS One (October 2012 issue).6
Protection from Alzheimer's disease

Claims were made for many years that regular fish oil consumption would help prevent people from developing Alzheimer's disease. However, a major study in 2010 found that fish oils and a placebo were no different in Alzheimer's prevention.

In contrast, a study published in Neurology in 2007 reported that a diet in fish, omega-3 oils, fruit and veggies reduces dementia and Alzheimer's risk.7
Protection from vision loss

Adequate dietary consumption of DHA protects people from age-related vision loss, Canadian researchers reported in the journal Investigative Ophthalmology & Visual Science.8
Benefits for the fetus

omega-3 consumption boosts fetal cognitive and motor development - scientists from L'Université Laval Laval found that omega-3 consumption by the mother during her last three months of pregnancy improved her baby's sensory, cognitive and motor development.

It is an effective pain reliever and has been linked to reduced risk of a number of health conditions, including heart attack, stroke and cancer. But is aspirin really the "wonder drug" many health experts claim it is?

Earlier this month, it was announced that researchers from the UK would be embarking on the biggest clinical trial of aspirin to date - the Add-Aspirin phase 3 trial - investigating whether the drug is effective for preventing cancer recurrence through a study of around 11,000 people.

The announcement has caused much excitement in the medical world, with many health experts claiming the trial could be "game-changing" if the drug is found effective, offering a non-expensive strategy to improve survival for cancer patients.

Cancer is just one in a long line of illnesses that aspirin may combat. But in the midst of potential health benefits comes a number of risks, a fact some health professionals believe is often overlooked.

"Because it's been around a long time people think 'it must be safe and it can't do me any harm,'" Prof. Peter Weissberg, medical director of the British Heart Foundation in the UK, told The Independent. "They are taking it 'just in case,' but it's much more dangerous than some other drugs which people get concerned about, like statins."

In this Spotlight, we take a closer look at the potential health benefits of aspirin, as well as the risks associated with the drug.
Aspirin: one of the most commonly used drugs worldwide

Aspirin is a drug that was developed by German research chemist Felix Hoffman, of pharmaceutical company Bayer, in 1897.

Hoffman created aspirin by developing a process to synthesize acetylsalicylic acid (ASA) - a synthetic derivative of a compound called salicin, which is found naturally in plants such as the willow tree.

Early clinical trials of aspirin found it was an effective treatment for pain, fever and inflammation. It is believed the drug produces these effects by inhibiting the production of pain-producing chemicals called prostaglandins. As such, aspirin is commonly used to help ease headache, muscle pain, toothaches and common colds, as well as swelling in arthritis.

More recently, however, researchers have discovered aspirin may also be an effective blood thinner, preventing the formation of blood clots in the arteries by blocking the production of a prostaglandin called thromboxane, which plays a key role in blood clotting.

As such, studies have shown daily aspirin therapy may lower the risk for heart attack and stroke, and it is often recommended for adults at high risk for these conditions.
The possible risks of aspirin use

However, as with any drug, there is a risk for side effects with regular aspirin use.

One of the most severe side effects of regular aspirin use is gastrointestinal bleeding, which can raise the risk of developing a stomach ulcer. If one already has a stomach ulcer, taking aspirin could cause further bleeding and be potentially life-threatening.

Aspirin may also interact with other drugs and increase risk of internal bleeding, particularly drugs with anti-clotting properties, such as warfarin, apixaban and dabigatran. Taking aspirin with some dietary supplements, such as evening primrose oil and fish oil, may also raise internal bleeding risk.

Some individuals are allergic to aspirin, with people who have asthma most at risk. An allergic reaction to the drug may cause swelling of the lips, mouth or throat, breathing problems and a skin rash.

Other side effects of aspirin include headache, nausea and vomiting, tinnitus and bruising.

Some studies have linked aspirin use with increased risk for other health conditions. In 2013, for example, a study published in JAMA Internal Medicine suggested long-term use of the drug may increase the risk of age-related macular degeneration - the primary cause of blindness among older adults.

Previous research has also linked aspirin use to greater risk for Reye's syndrome - a rare disorder characterized by swelling in the brain and liver, most common among children and teenagers.

Despite these potential risks, however, aspirin has become one of the most widely used over-the-counter drugs around the globe; more than 100 million standard aspirin tablets are produced every year.

But people are not just using the drug to relieve the odd headache or cold. It seems aspirin is growing in popularity as more people are taking the drug regularly with the aim of preventing numerous health conditions for which studies have suggested it is effective against.
Aspirin and heart health

As mentioned previously, one of the many benefits of aspirin is believed to be its ability to prevent the formation of blood clots.

Last year, Medical News Today reported on a study by researchers from Australia that found individuals with venous thromboembolism (VTE) - a condition comprised of deep vein thrombosis (blood clots in the legs) and pulmonary embolism (in which a blood clot breaks off and travels to the lungs) - saw a 42% reduction in blood clot recurrence with a 100-mg dose of aspirin daily.

This and numerous other studies hailing the anticoagulant properties of aspirin have led to recommendations that people at high risk for heart attack or stroke may benefit from daily aspirin therapy.

The American Heart Association (AHA), for example, recommend daily low-dose aspirin - under the instruction of a health care provider - for heart attack survivors and others at high risk of heart attack.

Supplements aren't for everyone, but older adults and others may benefit from specific supplements.
By Mayo Clinic Staff

The Dietary Guidelines for Americans make it clear that your nutritional needs should be met primarily through your diet.

For some people, however, supplements may be a useful way to get nutrients they might otherwise be lacking. But before you go shopping for supplements, get the facts on what they will and won't do for you.
Supplements vs. whole foods

Supplements aren't intended to be a food substitute because they can't replicate all of the nutrients and benefits of whole foods, such as fruits and vegetables. So depending on your situation and your eating habits, dietary supplements may not be worth the expense.

Whole foods offer three main benefits over dietary supplements:

    Greater nutrition. Whole foods are complex, containing a variety of the micronutrients your body needs — not just one. An orange, for example, provides vitamin C plus some beta carotene, calcium and other nutrients. It's likely these compounds work together to produce their beneficial effect.
    Essential fiber. Whole foods, such as whole grains, fruits, vegetables and legumes, provide dietary fiber. Most high-fiber foods are also packed with other essential nutrients. Fiber, as part of a healthy diet, can help prevent certain diseases, such as type 2 diabetes and heart disease, and it can also help manage constipation.
    Protective substances. Whole foods contain other substances important for good health. Fruits and vegetables, for example, contain naturally occurring substances called phytochemicals, which may help protect you against cancer, heart disease, diabetes and high blood pressure. Many are also good sources of antioxidants — substances that slow down oxidation, a natural process that leads to cell and tissue damage.

Who needs supplements?

If you're generally healthy and eat a wide variety of foods, including fruits, vegetables, whole grains, legumes, low-fat dairy products, lean meats and fish, you likely don't need supplements.

However, the dietary guidelines recommend supplements — or fortified foods — in the following situations:

    Women who may become pregnant should get 400 micrograms a day of folic acid from fortified foods or supplements, in addition to eating foods that naturally contain folate.
    Women who are pregnant should take a prenatal vitamin that includes iron or a separate iron supplement.
    Adults age 50 or older should eat foods fortified with vitamin B-12, such as fortified cereals, or take a multivitamin that contains B-12 or a separate B-12 supplement.
    Adults age 65 and older who do not live in assisted living or nursing homes should take 800 international units (IU) of vitamin D daily to reduce the risk of falls.

Dietary supplements also may be appropriate if you:

    Don't eat well or consume less than 1,600 calories a day.
    Are a vegan or a vegetarian who eats a limited variety of foods.
    Don't obtain two to three servings of fish a week. If you have difficulty achieving this amount, some experts recommend adding a fish oil supplement to your daily regimen.
    Are a woman who experiences heavy bleeding during your menstrual period.
    Have a medical condition that affects how your body absorbs or uses nutrients, such as chronic diarrhea, food allergies, food intolerance, or a disease of the liver, gallbladder, intestines or pancreas.
    Have had surgery on your digestive tract and are not able to digest and absorb nutrients properly.

Talk to your doctor or a dietitian about which supplements and what doses might be appropriate for you. Be sure to ask about possible side effects and interactions with any medications you take.
Choosing and using supplements

If you decide to take a vitamin or mineral supplement, consider these factors:

    Check the label. Read labels carefully. Product labels can tell you what the active ingredient or ingredients are, which nutrients are included, the serving size — for example, capsule, packet or teaspoonful — and the amount of nutrients in each serving.
    Avoid megadoses. In general, choose a multivitamin-mineral supplement that provides about 100 percent of the Daily Value (DV) of all the vitamins and minerals, rather than one which has, for example, 500 percent of the DV for one vitamin and only 20 percent of the DV for another.
    Check expiration dates. Dietary supplements can lose potency over time, especially in hot and humid climates. If a supplement doesn't have an expiration date, don't buy it. If your supplements have expired, discard them.
    Watch what you eat. Vitamins and minerals are being added to a growing number of foods, including breakfast cereals and beverages. If you're also taking supplements, you may be getting more than you realize of certain nutrients. Taking more than you need is expensive and can raise your risk of side effects. For example, too much iron can cause nausea and vomiting and may damage the liver and other organs.

Keep up with supplement safety alerts

The Food and Drug Administration (FDA) keeps a list of dietary supplements that are under regulatory review or that have been reported to cause adverse effects. If you're taking a supplement, it's a good idea to check the FDA website periodically for updates.

Vitamin C is a water-soluble vitamin, meaning that your body doesn't store it. You have to get what you need from food, including citrus fruits, broccoli, and tomatoes.

You need vitamin C for the growth and repair of tissues in all parts of your body. It helps the body make collagen, an important protein used to make skin, cartilage, tendons, ligaments, and blood vessels. Vitamin C is needed for healing wounds, and for repairing and maintaining bones and teeth. It also helps the body absorb iron from nonheme sources.

Vitamin C is an antioxidant, along with vitamin E, beta-carotene, and many other plant-based nutrients. Antioxidants block some of the damage caused by free radicals, substances that damage DNA. The build up of free radicals over time may contribute to the aging process and the development of health conditions such as cancer, heart disease, and arthritis.

It’s rare to be seriously deficient in vitamin C, although evidence suggests that many people may have low levels of vitamin C. Smoking cigarettes lowers the amount of vitamin C in the body, so smokers are at a higher risk of deficiency.

Signs of vitamin deficiency include dry and splitting hair; gingivitis (inflammation of the gums) and bleeding gums; rough, dry, scaly skin; decreased wound-healing rate, easy bruising; nosebleeds; and a decreased ability to ward off infection. A severe form of vitamin C deficiency is known as scurvy.

Low levels of vitamin C have been associated with a number of conditions, including high blood pressure, gallbladder disease, stroke, some cancers, and atherosclerosis, the build up of plaque in blood vessels that can lead to heart attack and stroke. Getting enough vitamin C from your diet -- by eating lots of fruit and vegetables -- may help reduce the risk of developing some of these conditions. There is no conclusive evidence that taking vitamin C supplements will help or prevent any of these conditions.

Vitamin C plays a role in protecting against the following:

Heart Disease

Results of scientific studies on whether vitamin C is helpful for preventing heart attack or stroke are mixed. Vitamin C doesn't lower cholesterol levels or reduce the overall risk of heart attack, but evidence suggests it may help protect arteries against damage.

Some studies -- though not all -- suggest that vitamin C can slow down the progression of atherosclerosis (hardening of the arteries). It helps prevent damage to LDL ("bad") cholesterol, which then builds up as plaque in the arteries and can cause heart attack or stroke. Other studies suggest that vitamin C may help keep arteries flexible.

In addition, people who have low levels of vitamin C may be more likely to have a heart attack, stroke, or peripheral artery disease, all potential results of having atherosclerosis. Peripheral artery disease is the term used to describe atherosclerosis of the blood vessels to the legs. This can lead to pain when walking, known as intermittent claudication. But there is no evidence that taking vitamin C supplements will help.

The best thing to do is get enough vitamin C through your diet. That way, you also get the benefit of other antioxidants and nutrients contained in food. If you have low levels of vitamin C and have trouble getting enough through the foods you eat, ask your doctor about taking a supplement.

High Blood Pressure

Population-based studies (which involve observing large groups of people over time) suggest that people who eat foods rich in antioxidants, including vitamin C, have a lower risk of high blood pressure than people who have poorer diets. Eating foods rich in vitamin C is important for your overall health, especially if you are at risk for high blood pressure. The diet physicians most frequently recommend for treatment and prevention of high blood pressure, known as the DASH (Dietary Approaches to Stop Hypertension) diet, includes lots of fruits and vegetables, which are loaded with antioxidants.

Common Cold

Despite the popular belief that vitamin C can cure the common cold, scientific evidence doesn't support that theory. Taking vitamin C supplements regularly (not just at the beginning of a cold) produces only a small reduction in the duration of a cold (about 1 day). The only other piece of evidence supporting vitamin C for preventing colds comes from studies examining people exercising in extreme environments (athletes, such as skiers and marathon runners, and soldiers in the Arctic). In these studies, vitamin C did seem to reduce the risk of getting a cold.

Cancer

Results of many population-based studies suggest that eating foods rich in vitamin C may be associated with lower rates of cancer, including skin cancer, cervical dysplasia (changes to the cervix which may be cancerous or precancerous, picked up by pap smear), and, possibly, breast cancer. But these foods also contain many beneficial nutrients and antioxidants, not only vitamin C, so it's impossible to say for certain that vitamin C protects against cancer. Taking vitamin C supplements, on the other hand, has not been shown to have any helpful effect.

In addition, there is no evidence that taking large doses of vitamin C once diagnosed with cancer will help your treatment. In fact, some doctors are concerned that large doses of antioxidants from supplements could interfere with chemotherapy medications. More research is needed. If you are undergoing chemotherapy, talk to your doctor before taking vitamin C or any supplement.

Osteoarthritis

Vitamin C is essential for the body to make collagen, which is part of normal cartilage. Cartilage is destroyed in osteoarthritis (OA), putting pressure on bones and joints. In addition, some researchers think free radicals -- molecules produced by the body that can damage cells and DNA -- may also be involved in the destruction of cartilage. Antioxidants such as vitamin C appear to limit the damage caused by free radicals. However, no evidence suggests that taking vitamin C supplements will help treat or prevent OA. What the evidence does show is that people who eat diets rich in vitamin C are less likely to be diagnosed with arthritis.

Taking nonsteroidal anti-inflammatory drugs can lower your levels of vitamin C. If you take these drugs regularly for OA, you might want to take a vitamin C supplement.

Age-related Macular Degeneration

Vitamin C (500 mg) appears to work with other antioxidants, including zinc (80 mg), beta-carotene (15 mg), and vitamin E (400 IU) to protect the eyes against developing macular degeneration (AMD), the leading cause of legal blindness in people over 55 in the United States. The people who seem to benefit are those with advanced AMD. It isn't known whether this combination of nutrients helps prevent AMD or is beneficial for people with less advanced AMD. This combination includes a high dose of zinc, which you should only take under a doctor’s supervision.

Pre-eclampsia

Some studies suggest that taking vitamin C along with vitamin E may help prevent pre-eclampsia in women who are at high risk. Pre-eclampsia, characterized by high blood pressure and too much protein in the urine, is a common cause of premature births. Not all studies agree, however.

Asthma

Studies are mixed when it comes to the effect of vitamin C on asthma. Some show that low levels of vitamin C are more common in people with asthma, leading some researchers to think that low levels of vitamin C might increase the risk for this condition. Other studies seem to show that vitamin C may help reduce symptoms of exercise-induced asthma.

Other

Although the information is limited, studies suggest that vitamin C may also be helpful for:

• Boosting immunity
• Maintaining healthy gums
• Improving vision for those with uveitis (an inflammation of the middle part of the eye)
• Treating allergy-related conditions, such as asthma, eczema, and hay fever (called allergic rhinitis)
• Reducing effects of sun exposure, such as sunburn or redness (called erythema)
• Alleviating dry mouth, particularly from antidepressant medications (a common side effect from these drugs)
• Healing burns and wounds
• Decreasing blood sugar in people with diabetes
• Some viral conditions, including mononucleosis -- Although scientific evidence is lacking, some doctors may suggest high-dose vitamin C to treat some viruses

Precautions

Because of the potential for side effects and interactions with medications, you should take dietary supplements only under the supervision of a knowledgeable health care provider.

Vitamin C supplements have a diuretic effect, meaning the help the body get rid of excess fluid. Be sure to drink plenty of fluids when taking them.

Most commercial vitamin C is made from corn. People sensitive to corn should look for alternative sources, such as sago palm.

Vitamin C increases the amount of iron absorbed from foods. People with hemochromatosis, an inherited condition where too much iron builds up in the body, should not take vitamin C supplements.

Vitamin C is generally considered safe because your body gets rid of what it does not use. But at high doses (more than 2,000 mg daily) it can cause diarrhea, gas, or stomach upset. If you experience these side effects, lower the dose of vitamin C.

People with kidney problems should talk to their doctor before taking vitamin C.

People who smoke or use nicotine patches may need more vitamin C because nicotine makes vitamin C less effective in the body.

Infants born to mothers taking 6,000 mg or more of vitamin C may develop rebound scurvy because their intake of vitamin C drops after birth. If you are pregnant, talk to your doctor before taking more than 1,000 mg of vitamin C.

People with sickle cell anemia, as well as people with a metabolic disorder called G6PD, can potentially have serious side-effects from taking high levels of vitamin C.

Thalassemia and Hemochromatosis patients could be negatively affected by increased iron absorption, which may occur from vitamin C supplementation.

Vitamin C may raise blood sugar levels in people with diabetes. In older women with diabetes, doses of vitamin C above 300 mg per day were associated with an increased risk of death from heart disease.

Taking vitamin C right before or after angioplasty may interfere with healing.

If you are being treated for cancer, talk to your oncologist before taking vitamin C. Vitamin C may potentially interact with some chemotherapy drugs

 Coriander is the dried seed of the cilantro plant. The whole seeds look like tiny round balls and are commonly ground into a powder and used for seasoning food.

Coriander has a multifaceted flavor profile and can be used in many types of recipes. It is most commonly found in Indian cuisine but can be paired with anything from salad dressing to barbecue rub.

This MNT Knowledge Center feature is part of a collection of articles on the health benefits of popular foods. It provides a nutritional breakdown of coriander and an in-depth look at its possible health benefits, how to incorporate more coriander into your diet and the potential health risks of consuming coriander.
Nutritional breakdown of coriander

According to the US Department of Agriculture (USDA) National Nutrient Database1, two tablespoons of ground coriander seed contain 30 calories, 1.2 grams of protein, 1.8 grams of fat, and 5.6 grams of carbohydrates (including 4 grams of fiber and 0 grams of sugar). That same 2 tablespoon serving provides 68% of your daily vitamin K needs, 10% of iron, 8% of calcium, and 4% of vitamin C.
Possible health benefits of consuming coriander

Below we take a look at the possible health benefits of coriander.
Anticancer effects
Cilantro leaves and coriander seeds.


A study reported in the American Journal of Clinical Nutrition suggests that common spices - including coriander - can inhibit heterocyclic amine (HCA) formation in meats during cooking. HCAs, defined by the National Cancer Institute, are chemicals formed when meat is cooked at high temperatures.2 A high consumption of foods containing HCAs is associated with higher risk of cancer.

These anticancer effects were demonstrated further in a different study published in the Journal of Food Science, in which five Asian spices, including coriander, were used to cook meats. The meats cooked with those spices had a significant decrease in HCA formation.2
Carotenoids

Dietary carotenoids can decrease the risk of numerous conditions, including several cancers and eye disease, due to their role as antioxidants.3 A study published in Plant Foods for Human Nutrition showed that basil and coriander contained the highest levels of the carotenoids beta-carotene and beta-cryptoxanthin as well as lutein and zeaxanthin, all known for their antioxidant abilities.2
How to incorporate more coriander into your diet
A bowl of carrot and coriander soup.


Coriander has a versatile flavor profile and can be used in anything from dressings and sauces to meat rubs and even desserts.

Whole coriander seeds can be stored in airtight containers for 1-2 years and ground coriander seeds can be stored in airtight containers for 6 months.

Quick tips:

    Add coriander into spice mixtures such as curry or barbecue rub
    Make a homemade dressing using part oil, part vinegar and seasonings including coriander
    Change up your go-to marinades by adding coriander.