The Vitamin Myth: Are Food Supplements Really Necessary?

Multivitamins, herbal remedies, cod liver oil—chances are, you’ve taken some kind of food supplement recently. In fact, surveys show that around 80% of Europeans have used a supplement in their lives, hoping to maintain, restore, or boost their health.

Globally, the supplement industry is booming, with estimates suggesting it could be worth between €60 billion and €184 billion.^2,3 In Europe, the Vitamins & Minerals market alone is projected to generate a revenue of approximately €4.79 billion in 2024, with an expected annual growth rate of 5.81% between 2024 and 2029.^1,4

But do these pills, powders, and drops really live up to their promises? From glowing skin to better digestion and a good night’s sleep, how do we know which ones are effective, and which ones are just hype? With supplements flooding store shelves and filling online shopping carts, it raises the question: are we truly getting healthier, or are we just buying into the idea that better health comes in a bottle?

Let's dive into the popular supplements Vitamin D, fish oil, and one of the latest multivitamin powders to find out what's worth the investment—and what might not be.

The Vitamin D debate

When checking the daily recommended intake on supplement labels, it's crucial to think beyond just preventing deficiencies and focus on long-term health and wellness—two goals that aren't quite the same. But how do we know how much we actually need? Do we need supplements to avoid (seasonal) deficiencies? The ongoing debate over Vitamin D shows us that this isn't an easy question to answer.

We have a curious relationship with vitamin supplements, especially vitamin D, which many governments recommend during the winter months. Public Health England suggests that while enough vitamin D can be obtained from sunlight and a healthy diet in the warmer months, a daily supplement of 10 micrograms (μg) is important during autumn and winter.⁵ People who spend little time outdoors, wear skin-covering clothing, or have darker skin may need to take supplements all year to maintain healthy levels.⁶ With around 20% of people reportedly having low levels in the UK, it seems like sensible advice. But is this deficiency a true public health crisis, or are we blowing it out of proportion?⁷ 

The criteria for "low" Vitamin D levels vary widely. Some organisations set the bar at 1 μg/L, while others argue for 3 μg/L. Recent studies suggest 1.2 μg/L  may be enough for most people. Adding to the complexity, genetic factors greatly influence Vitamin D levels, making it tough to define deficiency, and potentially leading to unnecessary supplementation for those misdiagnosed.^8,9,10 

The idea of a "Pandemic of Vitamin D Deficiency" has fueled concern, but is the problem really that widespread—or are we just setting the bar too high? 

Read More: How are Vitamin D Supplements Made?

Can a tablet guarantee a healthy heart? It’s fishy… 

Fish oil supplements, often in the form of tablets or capsules, have gained popularity for their supposed benefits in protecting the heart, reducing inflammation, boosting mental health, and even extending life. This buzz has led Americans to spend over $1 billion annually on these over-the-counter supplements, rich in omega-3 fatty acids. 

However, the evidence supporting these heart health claims is inconsistent. A study published in the New England Journal of Medicine in November 2018 found that omega-3 supplements did not reduce the risk of heart attacks, strokes, or heart-related deaths in middle-aged men and women without known heart disease risk factors. Similarly, a 2013 study from the same journal reported no cardiovascular benefits for people with existing risk factors. That said, when researchers specifically examined people who don’t eat fish, the results indicated that fish oil supplements may help reduce cardiovascular risk. Beyond these health findings, the environmental cost of fish oil production is also significant. The extraction of anchovetas and other small fish from critical marine ecosystems contributes to overfishing and disrupts the food chain, threatening biodiversity and the sustainability of ocean life.^11,12

Superfood Powders: The New Multivitamin

Superfood powders have become a social media sensation, offering a trendy alternative to the traditional multivitamin pill and promising a wide range of benefits. A very popular and viral example of these is AG1®, previously known as Athletic Greens.

This powder is meant to be mixed with liquid and consumed daily, offering 75 ingredients, including vitamins, minerals, probiotics, plant-based compounds, and adaptogens. It's designed to support energy levels, gut health, immune function, and more.

Despite its flashy packaging, AG1 serves a purpose similar to any other multivitamin, delivering nutrients—often in amounts greater than what you actually need, as is also common with regular multivitamin pills. For example, it contains 467% of the daily recommended value of vitamin C and 1,100% of vitamin B7, with the excess simply being flushed out in urine.

Vitamins A, D, E, and K are fat-soluble, meaning excessive intake can be harmful. For example, smokers are cautioned against high doses of beta-carotene (a precursor to vitamin A) as it may increase the risk of lung cancer when accumulated. AG1 contains 139% of the recommended daily intake for vitamin A and 558% for vitamin E.¹³ While vitamins are often associated with health benefits, they aren't without risks—more isn't always better.¹⁴

The idea of taking a multivitamin like AG1 as "nutritional insurance" is appealing, but research suggests that most people already receive sufficient vitamins through their diet. Given AG1's price tag—nearly $100 per package, or about $3 per day—it is likely unnecessary for many. Experts advise against routine multivitamin use for disease prevention, suggesting that it’s often the healthiest individuals - the “worried well” - who benefit least from these supplements.¹⁴  

What about your age-old multivitamin pill? An independent panel from the National Institutes of Health has made it clear: there is insufficient evidence to support the idea that multivitamins can prevent chronic diseases or common conditions like colds. Major health organisations like the American Cancer Society and the American Heart Association agree, finding no real role for a daily multivitamin in preventing cancer or heart disease. Their advice: Stick to a balanced diet rich in a variety of foods—something far more effective than any pill.¹⁶

So… When Should You be Taking Supplements? 

Despite the overwhelming noise from successful marketing and a booming supplement industry, public health experts have been urging people for years to stop wasting money on dietary supplements.¹⁷ Countless studies have revealed that most food supplements don’t significantly improve health outcomes, whether it's preventing cognitive decline, heart disease, or cancer.¹⁸ There are, however, certain situations where supplements, when used under proper medical guidance and with attention to product labels and potential interactions with medications, can benefit your health. Here are some of the main ones:^19,20 

1. To Treat or Prevent a Nutrient Deficiency

If a blood test reveals that your body is low in a particular vitamin or mineral, such as vitamin D or iron, supplements can be helpful in correcting that deficiency. For example, people who follow a vegan diet or have a condition called pernicious anaemia are at greater risk of a vitamin B12 deficiency and may benefit from taking a supplement. If your body struggles to absorb nutrients, which can happen with conditions like celiac disease, Crohn’s disease, ulcerative colitis, or after bariatric surgery, supplements can play a key role in helping you meet your nutritional needs.

2. If You Are or May Become Pregnant

It's important to take 400 to 800 micrograms of folic acid daily if you could become pregnant and during the early months of pregnancy to help prevent major birth defects. Most prenatal multivitamins, which should be taken throughout pregnancy, contain this amount, and also supply other key nutrients such as iron, calcium and vitamin D.

3. If You’re in Middle or Old Age

As you age, your nutrient requirements may increase while your ability to absorb them and your appetite can decline, which may lead your doctor to recommend a supplement. For instance, older adults often struggle to absorb vitamin B12, and if you're at risk for bone loss, you may need a calcium and vitamin D supplement.

But… Why Do We Feel The Need To Take Them?

If there’s no strong evidence that supplements are necessary to live a healthy life and prevent deficiencies, why is the industry booming? Why do so many of us turn to supplements? Dr. Katie Suleta, a public health research, data, and education professional points to several factors—one of the biggest being how these products are marketed. After years of studying health sciences and the supplement industry, Dr. Katie Suleta has identified three common misconceptions in supplement marketing that explain why so many people believe supplements are essential for everyone.²¹

1. Is "Natural" Really Healthier?

There’s a common belief that if something is “natural,” it must be good for you. It’s a term that pops up all over supplement marketing, with brands often using words like "nature" or "pure" to imply that their products are healthy or even essential for optimal health. But just because a supplement contains a natural nutrient does not guarantee its safety—especially when it contains amounts far exceeding what you’d find in food. In fact, some supplements can even be harmful.¹⁵

Dr. Suleta uses the comparison of vitamin C and the flu shot to illustrate this point. Many people associate oranges with vitamin C’s supposed flu-fighting properties, but when comparing that to the flu shot—one is scientifically proven to prevent illness, while the other lacks evidence supporting its effectiveness against the flu despite marketing claims. The term "natural" may make supplements seem safer, but it does not guarantee better results.²¹

2. Is More Really Necessary?

Another common misconception is the belief that if a little of something is good, more must be great. But that’s not really how it works.

Our bodies are equipped to regulate how much of a vitamin or mineral we need, discarding the excess. This is why people often joke that supplements result in 'expensive pee.' Take vitamin C, for example: most adults only require 75 to 120 milligrams a day, yet many supplements contain doses as high as 1,000 milligrams. While water-soluble vitamins like C are simply flushed out, taking excessive amounts of fat-soluble vitamins, such as D, not only offers no extra benefit but can also pose health risks.²¹

3. The Urge to Act

We often feel like doing something is better than doing nothing, especially regarding health. This is known as the "action bias", Dr Suleta mentions. Many people think, "I’ll take extra vitamins, just in case. What’s the harm?" Additionally, taking a pill is often seen as a quicker and easier way to improve health compared to the effort of preparing a balanced meal, even if it only provides the feeling of making progress rather than delivering the same real benefits.

However, there can be risks. Excessive vitamin C can cause nausea and stomach cramps, while too much vitamin D can lead to kidney stones. Additionally, some supplements can interfere with medications—like St. John’s wort, which can impact birth control and chemotherapy. So, taking action isn’t always the best approach for your health.²¹

There is No Magic Pill

"Natural" doesn’t guarantee that a product is healthier, more isn’t always beneficial, and sometimes, doing nothing is the smartest choice. And of course, it’s always best to consult with your doctor before adding any supplements to your routine. Ultimately, there’s no magic pill for good health. Supplements can’t replace a balanced diet and an active lifestyle. Better health still comes from the fundamentals: eating well and staying active.