The food supplement market can feel like a dense jungle—full of exotic promises, bright packaging, and tempting claims. Buyers, lured by bold statements about the almost magical power of products to provide a burst of energy, induce sleep instantly, support cognitive focus, or even rejuvenate and defy the natural passage of time, are often left wanting more when the advertising promises deflate and their expectations remain unfulfilled.

In this information noise, how can you distinguish between scientifically-backed benefits and blatant marketing? The good news is that with the right tools, you can make informed decisions about the products you use to support your well-being.

This guide is like a map and compass. Step by step, we will show you how and where to look for reliable information, how to distinguish high-quality scientific evidence from the results of early studies, and what to pay attention to when choosing a specific product.

Key messages

• Start with science, not marketing. The most reliable sources of information are scientific databases like PubMed, not brand websites or popular blogs.

• Not all studies are equally valuable. Learn to distinguish the highest level of evidence, such as systematic reviews, from preliminary laboratory studies on animals. The results of the latter are not always confirmed in humans.

• A trustworthy brand is transparent. Look for information about manufacturing standards (GMP certificate), third-party testing, and a clear ingredient list without mysterious "proprietary blends."

• Avoid miraculous promises. Be especially wary of products that promise rapid and dramatic effects, rely solely on emotional testimonials, or do not specify the exact dosages of active ingredients.

• Consultation with a professional is essential. No general guidelines can ever replace the advice of a healthcare professional who has your personal health profile in front of them. If you are following specific health regimens, only a professional can give qualified advice tailored to your individual situation.

Our approach: how we select information

We believe the path to optimal wellness is paved with knowledge, not guesswork. Therefore, we are sharing the principles we follow ourselves when seeking answers. Our thinking is based on reliability, authoritativeness, and expertise — principles also applied by search engines like Google.

• Expertise. We delve into peer-reviewed scientific research and consult with experts in science and nutrition. It is important for us to understand not only what works, but why.

• Authoritative sources. We base our knowledge on information from the world's most respected health institutions, such as the U.S. National Institutes of Health (NIH) Office of Dietary Supplements, the European Food Safety Authority (EFSA), or the World Health Organization (WHO).

• Reliability. Our goal is to be a trustworthy guide. We aim to help you sift through the marketing noise by providing a balanced and unbiased framework to understand what the scientific evidence truly says about the benefits of specific ingredients.

Step 1: Where to find reliable information about supplements

A proper search begins not with a general web search, but with specialized, unbiased sources. This will help you avoid marketing tricks and get immediate access to reliable data.

Most reliable information sources:

• PubMed. This is like a giant online medical encyclopedia administered by the U.S. National Library of Medicine. Here you will find millions of scientific articles on almost any ingredient. It is the best starting point.

• Google Scholar. An excellent tool for broadly searching scientific literature, from articles and dissertations to books.

Sources to approach with caution:

• Popular health blogs. Although they can sometimes be useful for a general understanding, they often simplify or misinterpret scientific data. Therefore, they should not be your primary source of information; it's always worth checking their conclusions in reliable, science-based sources.

• Brand websites. Remember, their primary goal is to sell. Information here will naturally be presented in the most favorable light.

• Social media and influencers. This is often the least reliable source. Recommendations are frequently based on promotional agreements rather than rigorous science.

Step 2: How to understand scientific evidence

Not all studies carry the same weight. Imagine a pyramid of evidence: the higher the level, the more reliable the data.

• The gold standard: systematic reviews and meta-analyses. This is the highest level of analysis, where scientists collect and summarize the results of all high-quality studies conducted on the same topic. This is the most reliable way to find out what science says about a particular compound.

• High level: randomized controlled trials. These are studies involving people where one group receives the test ingredient and another receives a placebo (a substance with no effect). This allows for an objective evaluation of the ingredient's effectiveness.

• Medium level: observational studies. These studies observe large groups of people and look for connections between their lifestyle (e.g., diet) and well-being. They can show a correlation, but do not strictly prove causation.

• Initial level: animal trials and laboratory studies. This is an important first step, but results in a lab setting are not always directly confirmed in humans.

Step 3: How to evaluate a brand

Once you are sufficiently familiar with a certain ingredient, it's time to evaluate the product itself and its manufacturer. A reliable brand will always be transparent.

What to look for:

• Third-party laboratory tests. This is an essential feature of high-quality formulations. When choosing a product, look for evidence that it has been tested by an independent laboratory to confirm its purity and ensure it is free of heavy metals or contaminants.

• Good Manufacturing Practices (GMP) certificate. This is one of the most important quality markers in the industry. A GMP certificate means that the facility where the product was produced meets the strictest international quality and safety standards.

• Clear label. Avoid products with proprietary blends, which hide the exact doses of the ingredients. A reliable manufacturer will always state the precise amount of each active component.

Step 4: Consult a specialist

No information on the internet can replace a conversation with your doctor or pharmacist. Before starting any new nutritional routine, it is highly recommended to consult with a specialist.

This is important because a healthcare professional can:

• Assess whether the specific compound aligns with your goals.

• Check if it will interact with other health regimens you are currently following.

• Recommend an optimal and appropriate dose.

• Help monitor your body's response over time.

Practice: how to learn about popular ingredients

Let's apply the steps we've discussed in practice. We will examine three popular ingredients: melatonin, L-theanine, and Rhodiola rosea.

Melatonin

1. Search. In the PubMed database, we search for phrases like "melatonin" or "melatonin sleep latency."

2. Evidence. There is strong scientific evidence (many systematic reviews) that melatonin is effective for circadian rhythm adjustments, such as when traveling across several time zones. However, studies show that while it may help you fall asleep faster, it is generally less impactful for addressing prolonged nighttime restlessness or total sleep duration.

3. Brand evaluation. When choosing a melatonin product, the dose is most important. Studies show that even very small doses (0.3-1 mg) are effective. A reliable manufacturer will offer a product with a clearly stated, appropriate dose and have third-party tests confirming purity.

4. Consultation. This is especially important because in many EU countries, higher doses of melatonin are strictly regulated. It is highly recommended to consult a professional to discuss appropriate usage.

L-Theanine

1. Search. In Google Scholar or PubMed, we search for the ingredient itself or for phrases related to its effects, such as "L-theanine caffeine interaction" or "L-theanine caffeine cognitive performance."

2. Evidence. There are numerous high-quality clinical trials confirming the synergistic effect of L-theanine and caffeine. Studies show that caffeine provides energy and alertness but can cause overstimulation or restlessness in some people. L-theanine acts as its partner — it promotes relaxation and increases alpha wave activity in the brain without causing drowsiness. Scientific articles note that this combination helps achieve a state of "calm focus," supporting attention while rounding out the sharper edges of caffeine.

3. Brand evaluation. When choosing a product with a combination of L-theanine and caffeine, it is important to pay attention to their ratio. Studies show that the optimal ratio is often about 2:1 in favor of L-theanine (e.g., 200 mg of L-theanine to 100 mg of caffeine). A reliable manufacturer clearly indicates both amounts.

4. Consultation. Although L-theanine is considered a very safe substance, its combination with caffeine may not be suitable for people with specific cardiovascular sensitivities. It is always best to consult a professional before use.

Rhodiola rosea

1. Search. In PubMed, we search for "Rhodiola rosea", or more specifically "Rhodiola rosea daily tension" or "Rhodiola rosea endurance."

2. Evidence. Such a search yields many studies and systematic reviews exploring the effectiveness of rhodiola as an adaptogen. Adaptogens are substances explored for their ability to help the body maintain balance amidst physical and mental demands. Scientific research suggests it can help support endurance and maintain a balanced mood during demanding periods.

3. Brand evaluation. When choosing a rhodiola botanical, standardization is essential. Look for a product whose label indicates the exact amount of active compounds — rosavins (usually 3%) and salidrosides (usually 1%). This is a key indicator of quality.

4. Consultation. Like other adaptogens, rhodiola can have a mildly stimulating effect. It is recommended to consult a doctor, especially if you have specific mood-related concerns or are following specific health regimens.

Summary: be an informed consumer

To successfully navigate the world of nutritional support, we must cultivate a healthy skepticism and rely on facts. By prioritizing scientific sources, understanding the differences in research quality, evaluating brand transparency, and consulting with professionals, you can confidently choose the right products for your wellness journey, regardless of the marketing noise.

Such an approach will allow you to make decisions that are not only evidence-based but also beneficial for your long-term lifestyle goals.

Frequently asked questions

• Why can't I just trust the reviews on a product website? Reviews on a brand's website may be curated. While customer experience is a great indicator of satisfaction, it remains subjective and does not replace scientific evidence. Look for reviews on independent platforms to get a broader picture.

• What is the difference between a proprietary blend and clear labeling? Clear labeling indicates each ingredient and its exact dose. A "proprietary blend" lists the ingredients but only provides the total weight of the entire mixture. This lack of transparency can sometimes mask lower amounts of the key active components.

• If a supplement is all-natural, does that mean it's inherently safe? Not necessarily. Natural is a marketing term, not an absolute guarantee. Many botanical substances can have strong effects or interact with other routines. The suitability of any product depends on the specific compound, the dose, and your individual profile, which is why consulting a professional is so valuable.

• How can I quickly check if a PubMed study is of high quality? When you find a study, review its title and abstract. Look for keywords such as randomized controlled trial, systematic review, or meta-analysis, which indicate higher-quality evidence. You can also use filters in the search results to isolate these specific types of studies.