Nutritional supplements cannot prevent depression, research shows

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A daily intake of nutritional supplements won't help stave off the onset of depression, a new study has revealed.

Instead, regular lifestyle coaching to help people improve their diets and eating behavior may provide a more effective method for people to prevent major depressive disorder.

The study is published in the Journal of the American Medical Association (JAMA) on Tuesday, March 5th 2019.

A team of international researchers, including Professor Ed Watkins from the University of Exeter, has conducted a pivotal new study into whether available in the High Street can play a role in preventing .

Experiencing often goes hand in hand with being overweight.

The study, called The MoodFood trial, compared different nutritional and lifestyle strategies that might change mood and wellbeing in people who were overweight defined as body mass index (BMI) > 25.

More than 1,000 overweight or obese participants from the UK, the Netherlands, Germany and Spain who were identified as being at elevated risk for depression—but were not currently depressed—took part in the study. Participants were followed up for one year.

Half of the study group received daily nutritional supplements, while the other half were given a placebo.

Half of the sample also received a psychological and behavioural therapy designed to help them change their habitual dietary behaviours and patterns. This included learning strategies to cope with low mood and to reduce snacking and to increase a healthy Mediterranean style diet.

The study found that the supplements, which contained folic acid, vitamin D, omega-3 fish oils, zinc and selenium, worked no better than the placebos in helping participants prevent depression over one year.

Although the behavioural therapy to encourage a healthy dietary behavior and improve diet was not effective at preventing depression overall, there was some evidence that it prevented depressive episodes in those participants who attended a recommended number of sessions.

This suggests the food-related behavioural therapy only works if the participants get a sufficient "dose" of therapy and are able to sufficiently change their diet and habitual dietary behaviours.

Professor Ed Watkins, an expert in Experimental and Applied Clinical Psychology at the University of Exeter said: "Because depression is such a common problem, finding effective and widely available ways to prevent depression at a population level is an important goal.

"Diet and nutrition held promise as one means to reach large numbers of people. However, this trial convincingly demonstrates that nutritional supplements do not help to prevent depression.

"There was a suggestion that changing food-related behaviour and diet may help to prevent depression, but this requires further investigation."

Given the increasing prevalence of depression, more people are actively searching for ways to decrease their risk through lifestyle modification, but are often overwhelmed by confusing and contradictory information.

The MooDFOOD prevention trial is the largest randomized clinical trial to study the effects of nutritional strategies on the prevention of .

Researcher Mariska Bot from Amsterdam UMC: reported "Daily intake of nutritional supplements over a year does not effectively prevent the onset of a major depressive episode in this sample.

Nutritional supplements were not better than placebo. Therapeutic sessions aimed at making changes towards a healthy dietary behaviour did also not convincingly prevent depression".

MooDFOOD project coordinators Professor Marjolein Visser and Professor Ingeborg Brouwer of the Vrije Universiteit Amsterdam said: "Based on a large number of studies and careful analysis, MooDFOOD researchers have come to three important conclusions at the end of their project.

"First, a healthy dietary pattern, typified by a Mediterranean style diet high in fruit, vegetables, wholegrains, fish, pulses and olive oil, and low in red meat and full-fat dairy products, may reduce the risk of developing depression. Second, in people with obesity, weight loss can lead to a reduction in depressive symptoms.

"Third, current evidence does not support the use of nutritional supplements in order to prevent depression."

These recent results have important implications for all Europeans. The MooDFOOD team has translated these findings into tools for the general population, health professionals (GPs, dieticians and psychologists), researchers and policy makers.

Explore further

Want to improve your mood? It's time to ditch the junk food

More information: Journal of the American Medical Association (2019). DOI: 10.1001/jama.2019.0556

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Citation: Nutritional supplements cannot prevent depression, research shows (2019, March 5) retrieved 23 October 2019 from
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Mar 05, 2019
How disgusting.
I thought only in the USA the researchers did propaganda for the pharmaceuticals.
What kind of study publishes against "the supplements", what kind of research is that!

How many supplements did they use? There are THOUSANDS of supplements, so how come they prove them ALL wrong? Did they use the ones that are world wide known to alleviate depression? like St john wort? Turmeric?

Also, anyone who does research with molecules knows that a proper study needs to present a placebo, versus different concentrations of the molecules, otherwise you might not get the effective dose, and can wrongly conclude that the molecule is ineffective.

That is why psychology has bad fame, for doing mediocre or bad research and try to push it with authority fallacies: "Professor Ed Watkins, an expert in Experimental and Applied Clinical Psychology at the University of Exeter". Expert my ass.

Mar 05, 2019
This appears to be a badly-designed experiment, or a poorly-written article, or both. The source article is pay-walled, and it's not worth 35 dollars to learn if there's much merit in the study.

Psychology has a reputation as a haven for students who can't make it in the hard sciences, and who often are attracted to the field because they have serious psychological problems of their own. This article reinforces that reputation

Mar 05, 2019
Mushrooms are food aren't they?

FDA Puts 'Magic Mushroom' Ingredient on Fast Track for Depression Treatment

Magic mushrooms: Treating depression without dulling emotions

Mar 05, 2019
It's a badly designed experiment. No micronutrients like potassium or magnesium, or other water soluble nutrients which may be depleted by excessive intake of diuretics like caffeine and alcohol.

A good diet is great, especially to get around carb crashes from poor diets which may exacerbate the situation, but not everyone can get coaching and getting a good footing to change dietary habits is essential.

Mar 05, 2019

The summaries of earlier research can be found at:


This includes summaries showing low omega 3 levels and vitamin D are associated with depression.

The summary at the journal site does not mention zinc: "1412-mg omega-3 fatty acids, 30-μg selenium, 400-μg folic acid, and 20-μg vitamin D3 plus 100-mg calcium".

This is only 800IU of vitamin D. There's plenty of research at the "Vitamin D Council" site suggesting that intake should be at least 5 times this. I guess the omega 3 dosage is equivalent to about 4 grams of fish oil.

Most people's potassium / sodium ratio is too low, causing hypertension and increased risk of stroke ("Sodium-to-Potassium Ratio and Blood Pressure, Hypertension, and Related Factors", "Dietary Sodium to Potassium Ratio and Risk of Stroke in a Multiethnic Urban Population"). The US RDA for potassium is 4.7 grams. (Continued . . .)

Mar 05, 2019
As far as I know the only practical way to get significant potassium via supplements is four or so small drinks of potassium gluconate solution throughout the day. I take 2.4 grams a day like this = 14.4 grams of potassium gluconate. (Check with your doctor and ramp up slowly.) Since this ratio affects the ionic balance and trans-membrane voltage of all cells, it wouldn't be surprising if it affects all aspects of health, including depression and anxiety.

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