The 60-second summary
Folic acid is the clear standard when trying to conceive. Vitamin D is useful if a deficiency is likely or proven, not as a blind high-dose experiment. CoQ10 is optional, costly and the evidence is mixed; if anything, any benefit appears mainly in certain ART situations rather than as a general booster.
- Folic acid: yes, start early and take consistently.
- Vitamin D: targeted — ideally weigh the risk or measure levels first.
- CoQ10: if at all, use for a limited time and with realistic expectations.
Why people often over-supplement when trying to conceive
Many reach for supplements because it makes them feel proactive. That is understandable, but there is a downside: the bigger the pile, the more likely overlaps, unnecessarily high total doses and a false sense of security.
Good supplement decisions follow a simple logic. First the standard, then risk factors, then diagnostics. Everything else quickly becomes a subscription that answers no clear question.
Folic acid: the standard that really matters
Folic acid has the clearest evidence base. Its goal is not a vague increase in fertility but supporting very early developmental steps at a time when many people do not yet know they are pregnant.
Health authorities generally recommend taking 400 µg of folic acid daily when trying to conceive, ideally starting at least four weeks before pregnancy and continuing through the end of the first trimester. Health Canada: Folic acid for women who may become pregnant
Typical mistakes that matter more than the brand
- Starting too late and hoping a few days will make up the difference.
- Taking it irregularly because you don’t feel an immediate effect.
- Buying a prenatal without checking how much folic acid it actually contains.
- Increasing the dose without a clear medical reason.
If you have particular risk factors, take certain medications or have pre-existing conditions, recommendations may differ. In those cases it makes sense to get medical advice before increasing the dose yourself.
Vitamin D: useful, but rarely worth flying blind
Vitamin D is often marketed as a fertility booster. In practice it is primarily a deficiency issue. It can be useful when levels are likely low, and it is unnecessary when you are already adequately supplied.
Nutrition guidance notes that reference intake values are particularly relevant when endogenous production from sunlight is reduced. That is a good reminder why season, daily routines and time spent outdoors should factor into the decision. Health Canada: Reference values for vitamin D
When vitamin D is more likely to be an issue
- Little sun exposure for extended periods, especially during winter months.
- A mainly indoor lifestyle with rare time spent outdoors.
- Individual factors or medical conditions that make a low level more likely.
Avoid very large single doses taken days or weeks apart as a shortcut. Regulatory bodies have warned that such bolus dosing can carry health risks, especially without clear indication and monitoring. Health Canada: Risks of high single doses of vitamin D
CoQ10: what it’s advertised for and what is realistic
CoQ10 is often promoted for cellular energy and antioxidant effects. From that springs the claim that it generally improves egg quality or increases pregnancy chances. That sounds plausible, but as a blanket recommendation it is not well established.
In studies CoQ10 appears mainly as a possible option in certain assisted reproductive technology (ART) contexts. A systematic review with meta-analysis found signals of benefit for some outcomes in ART settings, while evidence remains limited by study design and comparability. PubMed: CoQ10 and outcomes in ART
When CoQ10 might at most make sense
- As a time-limited option when ART is planned and you accept the uncertainty.
- When budget, tolerability and expectations align.
When CoQ10 is less appropriate
- If you want it to replace diagnostics or medical evaluation.
- If taking it becomes a compulsory routine that creates pressure.
- If you combine multiple products and total doses become unclear.
A good reality check is: if a product sounds like a must despite mixed data, it is usually marketing rather than a standard.
Other dietary supplements: what is often useful and when it’s marketing
After folic acid, vitamin D and CoQ10, the next recommendations often come from social media or forums. Many have a plausible basis, but they quickly become generalized. The key question is whether you have a clear situation that makes the supplement relevant.
Iodine
Iodine can be a relevant issue in pregnancy and breastfeeding because requirements increase. At the same time, people with thyroid disease should only take iodine under medical supervision, not by self-medication.
Iron
Iron is frequently promoted indiscriminately. It is mainly useful for proven deficiency or anaemia. Without evidence, high-dose intake is more likely to cause side effects than benefit.
Vitamin B12
B12 is particularly relevant for vegan diets. In that case reliable supplementation is usually necessary. With an omnivorous diet it depends more on individual factors, and a check can give more clarity than buying blindly.
Omega-3, DHA, choline
These nutrients are heavily marketed but are rarely the first adjustment. For many people the pragmatic approach is to review the diet and supplement for gaps rather than automatically starting the next stack.
Zinc, selenium, antioxidant complexes
With these especially: more is not necessarily better. Individual trace elements can be important in true deficiencies; as a blanket booster they are often oversold and overdoses are possible.
Inositol and other specialised products
Such products can be considered for certain diagnoses, for example in PCOS. Without a diagnosis and a plan for how to evaluate effects they quickly become expensive noise.
Myths and facts: the most common errors in thinking
Most myths are not entirely false but overly simplistic. They turn a possible association into a guarantee. That leads to frustration and unnecessary expense when trying to conceive.
- Myth: The more supplements, the better. Fact: The more you combine, the higher the risk of overlaps, side effects and unclear total doses.
- Myth: High doses work faster. Fact: For some nutrients the risk increases faster than the benefit, especially without monitoring.
- Myth: An expensive product is automatically high quality. Fact: Price is not proof of quality and does not replace clear labelling.
- Myth: CoQ10 is mandatory. Fact: It is optional and the evidence is mixed, particularly outside clear ART contexts.
- Myth: Vitamin D always helps. Fact: It helps mainly when levels are actually low.
- Myth: If I supplement, I don’t need diagnostics. Fact: If pregnancy does not occur, investigation is often more effective than more products.
Minimal plan instead of a pill stack
A good plan is small, clear and sustainable. It reduces complexity instead of increasing it.
- Base: consistent folic acid.
- Targeted: vitamin D only with risk or confirmed deficiency; avoid high-dose experiments.
- Optional: CoQ10 time-limited if in an ART context and expectations are realistic.
If you want to add more, state the reason in one sentence beforehand. If you can’t, the addition is often marketing rather than medicine.
Safety: overdosing, interactions, false security
The biggest risk is rarely an acute emergency. More common are cumulative overdoses over time, unclear combinations and a deceptive sense of security that replaces diagnostics or lifestyle changes.
- Fat-soluble vitamins can become problematic at high doses.
- Multiple products taken together increase the risk of unintentionally reaching very high total doses.
- If you have chronic conditions or take regular medication, check new supplements beforehand.
A practical safety check is to place the labels of all products side by side and roughly add the total doses per nutrient.
Legal and regulatory context in Germany
Dietary supplements are legally classified as foods in Germany, not medicines. They are not approved like pharmaceuticals before sale, and initial responsibility for legal compliance lies with the manufacturer or importer.
The Federal Office for Consumer Protection and Food Safety explains classification and key rules around dietary supplements, including notification procedures before market entry. Health Canada: Dietary supplements
If you order internationally, note that rules, controls and permitted compositions can vary significantly by country. That is not a reason to panic, but it is a good reason to be cautious with extreme doses and questionable health claims.
When diagnostics are more useful than supplements
If trying to conceive remains unsuccessful for a longer time, the question is rarely which supplement is missing. More often the issue is whether there is an identifiable cause that can be treated specifically.
This is especially true with cycle irregularities, severe pain, known diagnoses, after recurrent miscarriages or when time is an important factor. In those situations a structured medical plan usually helps more than another purchase.
Conclusion
Folic acid is the standard and is worth starting early and taking consistently. Vitamin D is sensible when a deficiency is plausible or proven, not as a high-dose experiment. CoQ10 is optional and a conscious choice under uncertainty rather than a requirement.
When you build a plan, keep it small, understandable and feasible long term. In practice that is often more helpful than any pill stack.
Note on the classification of add-ons: In fertility medicine many additional offers and supplements are discussed as having limited evidence. The HFEA classifies many add-ons as not sufficiently evidence-based for routine use and calls for transparency about benefits and risks. HFEA: Treatment add-ons
