Taking fish oil supplements has no benefit in preventing or treating Type 2 diabetes, a large review of randomized clinical trials has found.
Some observational studies have suggested a positive effect for the supplements, which are high in omega-3 fatty acids, and they are widely promoted for diabetes control and prevention.
But this new analysis, commissioned by the World Health Organization and published in BMJ, included 83 trials involving 121,070 subjects with and without diabetes, mostly testing omega-3s against placebo. Omega-3s had little or no effect on the likelihood of a diabetes diagnosis, on average blood glucose levels over time, or on fasting insulin. There was some weak evidence that omega-3 doses above 4.4 grams a day could be harmful for people with diabetes.
The effects of two other polyunsaturated fatty acids — alpha-linoleic acid (ALA) and omega-6 fatty acids — were unclear. The researchers found no effect of either increasing total consumption of all types of polyunsaturated fatty acids, or of adjusting the ratio of omega-3s to omega-6s.
- Fish oil pills ‘no benefit’ for type 2 diabetes
- ‘Expensive stuff’
- Omega-3 vs diabetes: Walnuts & fish oil supplements deemed ineffective for treatment
- Cut Sugar, Lose Body Fat & Quit Smoking: Lifestyle Habits To Ditch Diabetes
- Far From Fin-ished: Fish Oil May Help Fight Type 2 Diabetes, But Link Unclear
- Miracle Cure for Diabetes
- Other Benefits of Omega-3 Fatty Acids
- Diabetes Forecast
- Effects of Fish Oil Supplementation on Glucose and Lipid Metabolism in NIDDM
- Omega-3 fats don’t reduce the risk of diabetes or improve blood sugar control
- Research we’re watching
Fish oil pills ‘no benefit’ for type 2 diabetes
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People with type 2 diabetes “should not be encouraged” to take omega-3 fish oil supplements, researchers from the University of East Anglia say.
There had been some concerns omega-3 could be harmful for people with the condition.
But while a BMJ review of more than 80 studies found no evidence of that, they also failed to find any benefit.
Diabetes UK said it was better to get omega-3 from eating oily fish as part of a healthy diet.
Most people with diabetes – 90% – have type 2, where the pancreas either fails to produce enough insulin or the body’s cells fail to react to insulin.
Being overweight or obese, or having a close relative with the condition increases the risk.
The researchers found omega-3 from fish oils had little or no effect on the likelihood of diabetes diagnosis or on glucose metabolism, no matter for how long people were studied.
Dr Lee Hooper, who led the research, told the BBC there had been concerns omega-3 supplements might harm people with type 2, by making glucose control more difficult.
But those with the condition, or who are at risk of developing it, can also have high levels of triglycerides – a type of blood fat – which omega-3 has been shown to reduce.
She said: “We found neither harm nor benefit.
“This is really expensive stuff. If somebody’s at risk of diabetes, there are much better things to spend money on, like a physical activity – or oily fish.”
Douglas Twenefour, deputy head of care at Diabetes UK, said: “Eating a healthy, varied diet is incredibly important, and we know that certain foods – including fruits, vegetables, wholegrains, yoghurt and cheese – can help to lower your risk of type 2 diabetes.
“While omega-3 fatty acids are crucial for our overall health, it’s generally better for people with type 2 diabetes to get their intake by eating at least two portions of oily fish a week, than by taking supplements.”
But Dr Carrie Ruxton, from the industry-funded Health and Food Supplements Information Service (HSIS), said: “While I would prefer people to follow the government’s advice and eat more fish, this isn’t the reality and a daily omega-3 supplement – whether from fish oil or algae – can bridge the gap.”
Omega-3 vs diabetes: Walnuts & fish oil supplements deemed ineffective for treatment
LONDON: If you are popping fish oil supplements to protect yourself against diabetes, you may be mistaken. According to the researchers, Omega-3 fats have little or no effect on risk of Type 2 diabetes.
Increased consumption of omega 3 fats is widely promoted because of a common belief that it will protect against, or even reverse, conditions such as diabetes.
According to the team from University of East Anglia (UEA), omega 3 supplements offer no benefit.
“Our previous research has shown that long-chain omega 3 supplements, including fish oils, do not protect against conditions such as heart disease, stroke or death. This review shows that they do not prevent or treat diabetes either,” said Dr Lee Hooper, from UEA’s Norwich Medical School.
“Omega-3 supplements should not be encouraged for diabetes prevention or treatment,” he added.
If people do choose to take supplementary fish oil capsules to treat or prevent diabetes, or to reduce levels of triglycerides in their blood, then they should use doses of less than 4.4 grams per day to avoid possible negative outcomes.
“The most trustworthy studies consistently showed little or no effect of long-chain omega 3 fats on diabetes,” said the paper.
Cut Sugar, Lose Body Fat & Quit Smoking: Lifestyle Habits To Ditch Diabetes
16 Feb, 2019Diabetes is among the fastest growing health issues today in India.The rising prevalence of diabetes is primarily driven by a combination of various factors such as rapid urbanisation, sedentary lifestyles, unhealthy diets, tobacco use, and even increased life expectancy.Although there are certain factors one can’t change such as your genes, age or past behaviours, but there are many actions one can take to reduce the risk of diabetes.Dr Varsha Khatry, Head – Medical and Scientific Affair at Roche Diabetes Care India shares some easy ways to not only reduce the risk of diabetes, but also prevent it.
Omega 3 is a type of fat. Small amounts are essential for good health and can be found in the food that we eat. Omega 3 fats are also readily available as over-the-counter supplements and they are widely bought and used.
The research team assessed the effects of long-chain omega-3 fats, ALA, omega-6 and polyunsaturated fatty acids (PUFAs) – taken as supplementary capsules, or via enriched or naturally rich foods.
Participants included men and women, some healthy and others with existing diabetes, from North America, South America, Europe, Australia and Asia, in studies published from the 1960s until 2018.
Participants were randomly assigned to increase their polyunsaturated fats or to maintain their usual intake for at least six months.
There was clearly no effect of increasing long-chain omega-3 fats on diabetes, but there was insufficient information from trials of ALA, omega-6 or total polyunsaturated fats to assess either protective or harmful effects.
The results show that increasing long-chain omega-3 had little or no effect on diabetes diagnosis or glucose metabolism, but high doses, at levels found in some supplements, could worsen glucose metabolism.
“Oily fish can be a very nutritious food as part of a balanced diet, but we did not find enough trials that encouraged participants to eat more oily fish to know whether it is useful in preventing diabetes or improving glucose metabolism,” said Dr Julii Brainard from Norwich Medical School.
“Future trials need to measure and assess baseline omega-3 intakes, and assess effects of eating more oily fish — not just supplements,” she added.
Far From Fin-ished: Fish Oil May Help Fight Type 2 Diabetes, But Link Unclear
WEDNESDAY, May 22, 2013 — There’s something fishy about the news that omega-3 supplements may help fight type 2 diabetes. Researchers believe fish oil can help with glucose regulation, but they don’t yet understand whether it has a direct impact on type 2 diabetes development, according to a study published in the Journal of Clinical Endocrinology & Metabolism.
Researchers at the Harvard School of Public Health reviewed data from 14 studies involving 1,323 subjects to determine the effects of fish oil supplements on diabetes risk factors. In total, 682 subjects had taken fish oil supplements. The researchers found that fish oil was associated with an increase in the level of the hormone adiponectin – which effects glucose regulation and inflammation. Their findings confirmed previous animal studies that also found fish oil can raise the level of adiponectin in the bloodstream.
Scott Drab, PharmD., CDE, BC-ADM, associate professor of pharmacy and therapeutics at the University of Pittsburgh, says people with diabetes can benefit from taking fish oil supplements. “Fish oil has anti-inflammatory properties, and because insulin resistance is associated with inflammation, we recommend fish oil to our patients,” said Dr. Drab. “Anything used as an anti-inflammatory can help glucose levels.”
Miracle Cure for Diabetes
It may help glucose levels, but the authors of the Harvard study were not convinced that the increase in adiponectin levels associated with fish oil could directly prevent type 2 diabetes.
“Although higher levels of adiponectin in the bloodstream have been linked to lower risk of diabetes, whether fish oil influences glucose metabolism and development of type 2 diabetes remains unclear,” said the study’s lead author, Jason Wu, PhD, in a press release. “However, results from our study suggest that higher intake of fish oil may moderately increase blood level of adiponectin, and these results support potential benefits of fish oil consumption on glucose control and fat cell metabolism.”
Despite his endorsement of fish oil supplements for people with diabetes, Drab doesn’t believe it’s the answer to the diabetes problem.
“It’s not our main treatment, but it’s another notch in the belt in the fight against diabetes,” Drab said. “Diet and exercise are probably better options than just taking fish oil.”
Other Benefits of Omega-3 Fatty Acids
This latest study of omega-3s study found a link between fish oil and diabetes. Other studies have found that they can be good for your health in other ways.
Omega-3 fatty acids have been shown to reduce the risk of prostate cancer and postpartum depression, help the brain function of Alzheimer’s patients, and treat autoimmune diseases.
Christy L. Parkin, MSN, RN, CDE, responds: There is no evidence that taking fish oil supplements leads to diabetes; in fact, numerous studies demonstrate the valuable benefits of omega-3 fatty acids, which are substances that the body needs but cannot produce on its own.
A great source of omega-3s is fish oil, which is extracted from cold-water fish such as salmon, mackerel, herring, and cod. One benefit of fish oil is improved cardiovascular health. Omega-3s reduce the risk for developing coronary heart disease. Their potent anti-inflammatory properties may not only help the heart but also ease symptoms of rheumatoid arthritis, Crohn’s disease, and inflammatory bowel disease. In addition, fish oil is used to treat depression, bipolar disorder, postpartum depression, anxiety, and schizophrenia. The Alzheimer’s Association recommends eating fish to protect against dementia.
So far, scientific evidence suggests that there are no significant long-term negative effects of fish oil in people with diabetes, including no changes in A1C levels, according to a Mayo Clinic report. However, some precautions should be taken when it comes to fish oil supplements. You should buy a pharmaceutical-grade, purified supplement to help guard against potentially harmful contaminants found in some species of fish. Problems with contaminants tend to arise when eating fish, not when taking supplements.
Other risks apply to specific groups of people. Young children and pregnant or nursing women should avoid the heavy metals that are found in some fish. High doses of omega-3 fatty acids may also increase the risk for bleeding.
Fish oil supplements often cause gastrointestinal upset, and diarrhea may occur, especially with very high doses. The supplements can also have a fishy aftertaste and increase burping, acid reflux, heartburn, and indigestion. You can minimize these side effects by taking the supplement with meals and starting with smaller doses.
According to the Food and Drug Administration, most people can safely take up to 3 grams (3,000 mg) per day of omega-3 fatty acids. Young children, pregnant and nursing women, people who are at risk for bleeding, and those who have high levels of LDL (“bad”) cholesterol may need to limit their intake of omega-3s in consultation with their doctor or dietitian.
Effects of Fish Oil Supplementation on Glucose and Lipid Metabolism in NIDDM
Fish oils, containing omega-3 fatty acids (ω3FAs), favorably influence plasma lipoproteins in nondiabetic humans and prevent the development of insulin resistance induced by fat feeding in rats. We studied the effects of fish oils in 10 subjects (aged 42–65 yr) with mild non-insulin-dependent diabetes mellitus (NIDDM). Subjects were fed a standard diabetic diet plus 1) no supplementation (baseline), 2) 10 g fish oil concentrate (30% ω3FAs) daily, and 3) 10 g safflower oil daily over separate 3-wk periods, the latter two supplements being given in radom order by use of a double-blind crossover design. At the end of each diet period, fasting blood glucose (FBG), insulin, and lipids were measured, and insulin sensitivity was assessed with a hyperinsulinemic-euglycemic clamp performed with glucose. FBG increased 14% during fish oil and 11% during safflower oil supplementation compared with baseline (P < .05), whereas body weight, fasting serum insulin levels, and insulin sensitivity were unchanged. The absolute increase in FBG during each supplementation period correlated with the baseline FBG (fish oil, r = .83, P < .005; safflower oil, r = .75, P = .012). Fasting plasma triglyceride levels decreased during fish oil supplementation in the 4 subjects with baseline hypertriglyceridemia (>2 mM) but were not significantly reduced overall. There was no significant change in fasting plasma total, high-density lipoprotein, and low-density lipoprotein cholesterol levels. In summary, dietary fish oil supplementation adversely affected glycemic control in NIDDM subjects without producing significant beneficial effects on plasma lipids. The effect of safflower oil supplementation was not significantly different from fish oil, suggesting that the negative effects on glucose metabolism may be related to the extra energy or fat intake. These data indicate that fish oil supplementation should be used with caution in subjects with NIDDM.
Omega-3 fats don’t reduce the risk of diabetes or improve blood sugar control
Research we’re watching
Published: December, 2019
While eating more foods rich in omega-3 fatty acids may lower the risk of heart attack, that doesn’t seem to reduce the risk of developing diabetes, according to a study published Aug. 24 in The BMJ. Prompted by past findings that this type of healthy fat might reduce diabetes risk and improve blood sugar (glucose) control, researchers decided to look further into the issue. They reviewed 83 randomized trials involving more than 120,000 people, both with and without diabetes. Each trial went on for six months or longer. These trials looked at whether increasing consumption of omega-3 fats (derived from fish or plants), omega-6 fats (such as those in soybean or corn oil), or total polyunsaturated fats could help lower blood glucose or reduce the risk of developing diabetes. They found that increasing the amount of omega-3, omega-6, or total polyunsaturated fats in the diet over an average study period of nearly three years didn’t seem to have any effect on glucose metabolism or diabetes risk. It didn’t matter whether the additional healthy fats came from supplements, enriched foods, or foods that were naturally rich in these fats.
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If you have diabetes, you may know that it increases your risk of diabetic retinopathy, one of the leading causes of blindness in American adults. It affects more than 5 percent of the U.S. population, but research suggests that omega-3 fatty acids in your diet could help protect your eyes.
More common among Hispanics and those over age 65, diabetic retinopathy occurs when blood vessels in the eyes swell and leak, or when abnormal cells grow on the retina and eventually block your vision.
As more people develop type 2 diabetes — and generally live longer — researchers are looking for a way to stave off retinopathy.
One good way is to keep blood sugar levels under control. And research suggests that omega-3 fatty acids, from food sources like fish and nuts and from supplements, are a powerful protector against this eye condition.
What research tells us about omega-3s
Research shows that omega-3 fatty acids may reduce the risk of cardiovascular disease and slow hardening of the arteries. In higher-risk populations, such as individuals with type 2 diabetes, the data is less conclusive.
But some research shows that the nutrient may work to decrease the chances that you will get diabetic retinopathy. A study published in the Journal of the American Medical Association examined more than 2,500 middle-aged and elderly people with type 2 diabetes. It found that those who consumed omega-3s regularly had a 48 percent lower risk of diabetic retinopathy than those who didn’t (after a six-year follow-up).
Scientists believe that omega-3s may help stave off retinopathy because the fatty acids protect against inflammation and the abnormal growth of blood vessels in the eyes.
Vitamins from food are best
As always, it’s best to get nutrients from food instead of supplements whenever possible. And you can get the recommended dose by eating just two servings of fish a week. Those high in omega-3 fatty acids include:
- Lake trout
- Albacore tuna
Not a fan of fish? There are plenty of other foods you can add to your shopping list that are high in omega-3s, including:
- Pumpkin seeds
- Flax seeds
- Brussels sprouts
- Canola oil
So, if you have diabetes, it’s a good idea to look through these lists and pick out some favorites. Then work a couple servings into your meals and snacks each week so you’re doing all you can to protect your eyes and guard against vision loss.
A note of caution
If you plan to take omega-3 fatty acids as a supplement, it’s important to note: The American Heart Association cautions against taking more than 3g capsules daily unless your doctor prescribes it. For some people, too much omega-3 fatty acid can cause excessive bleeding. Be sure to consult your practitioner.