

Medically Reviewed By Margaret Etudo. Written By The Vitamins For Woman Team.
While both are widely used, their roles in the body are vastly different. Here’s how to know which is right for you or if taking both could be your best bet.
In the ever-growing world of dietary supplements, fish oil and B vitamins are among the most recommended and widely consumed.
Whether it’s your doctor suggesting fish oil for heart health or a wellness influencer promoting B vitamins for energy and mental clarity, both supplements have earned a reputation for delivering tangible health benefits.
But the question remains: which is better, fish oil or B vitamins?
Fish oil is rich in omega-3 fatty acids, particularly EPA and DHA, which are linked to reduced inflammation, improved cardiovascular function, and even support for cognitive health.
Meanwhile, B vitamins, a family of eight essential nutrients, are pivotal in converting food into energy, supporting nervous system function, and maintaining healthy skin and red blood cell production.
Whether you’re trying to improve your energy levels, reduce inflammation, support your heart, or simply enhance your overall well-being, this detailed guide on fish oil vs. B vitamins will help you understand how they work, how they compare, and whether it makes sense to take them together.
Understanding the roles of each supplement reveals why they are often used for very different health goals.
Fish oil is derived from the fatty tissues of oily fish like salmon, mackerel, and sardines.
The active compounds in fish oil EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are long-chain omega-3 fatty acids known for their anti-inflammatory effects and critical role in maintaining cell membrane health.
These fatty acids are involved in everything from reducing triglyceride levels to improving arterial flexibility and supporting cognitive health as we age.
Fish oil also plays a role in supporting mental well-being. Research suggests that low levels of omega-3s are associated with mood disorders, including depression.
Increasing your intake of EPA and DHA can support emotional balance and cognitive performance, a benefit that becomes increasingly important during ageing and hormonal shifts such as menopause.
The B-complex family includes eight water-soluble vitamins: B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folate), and B12 (cobalamin).
Each one plays a unique role in your health, but collectively, they help your body metabolize food, produce energy, synthesize hormones and neurotransmitters, and keep your nervous system functioning smoothly.
For example, B12 and folate are essential for DNA synthesis and red blood cell formation. A deficiency in these can lead to fatigue, brain fog, and even depression.
B6 helps produce serotonin and dopamine, two neurotransmitters responsible for mood regulation. Without enough of these vitamins, your energy and mental clarity suffer, regardless of how clean your diet is.
Unlike fish oil, B vitamins don’t provide long-term anti-inflammatory benefits but give your body the tools it needs to run at full capacity.
In situations like stress, menopause, or hormonal imbalance, your need for B vitamins often increases.
While both supplements offer health advantages, one may be more suited for specific goals.
When it comes to cardiovascular protection, fish oil is the clear standout. Studies have shown that omega-3s can lower triglycerides, reduce blood pressure, improve arterial function, and reduce the risk of arrhythmias.
The research found that people who took daily fish oil supplements had a significantly lower risk of heart attacks and other major cardiovascular events.
Fish oil’s ability to fight inflammation is central to its heart-protective benefits. Chronic inflammation is a key driver of atherosclerosis, the hardening and narrowing of the arteries that leads to heart disease.
Omega-3s help maintain arterial elasticity and reduce plaque buildup by dampening inflammatory pathways.
B vitamins are unmatched if your goal is to improve daily energy levels and enhance emotional well-being.
Because they are involved in mitochondrial energy production, the process that turns food into usable energy, B-complex vitamins are critical for combating fatigue and sluggishness.
People who are deficient in B vitamins often report low energy, irritability, depression, and poor focus.
Supplementing with B12 and B6 has been shown to reduce symptoms of depression and anxiety, especially in women with hormonal imbalances.
Additionally, folate and B12 play a role in reducing homocysteine, an amino acid linked to cognitive decline and poor brain health.
These nutrients work synergistically to support mood stability, clear thinking, and sustained energy.
Research suggests combining fish oil and B vitamins could unlock even greater health benefits.
Yes, you can, and in many cases, you should take fish oil and B vitamins together. A growing body of research suggests that these supplements synergistically promote cognitive and cardiovascular health.
Studies show that individuals with higher omega-3 status who also took B vitamins had significantly less brain shrinkage over time than those who were only supplemented with B vitamins alone.
Another benefit of combining these two is their complementary support in reducing homocysteine, a known marker of cardiovascular disease.
While B vitamins (especially B6, B12, and folate) help metabolize homocysteine, omega-3s help reduce its associated inflammatory effects.
Together, they form a powerful team to protect the heart and brain.
Your health status, lifestyle, and diet can determine whether fish oil or B vitamins are better suited to your needs.
Vegans and vegetarians often miss out on key nutrients like B12, which is found only in animal products.
Over time, B12 deficiency can lead to nerve damage, fatigue, and cognitive issues. For plant-based eaters, a high-quality B-complex supplement is crucial for long-term vitality.
People with inflammation, joint pain, or autoimmune issues benefit more from fish oil’s anti-inflammatory omega-3s.
EPA and DHA help calm the body’s inflammatory response and may reduce symptoms without the side effects of pain meds.
B vitamins help support energy, mood, and adrenal function if you’re under chronic stress or feeling burnt out.
They get used up quickly during stress, so a B-complex can help restore balance and stabilize your nervous system.
Thanks to DNA’s role in memory and focus, fish oil protects brain health as you age.
It helps maintain brain structure and may slow cognitive decline more effectively when paired with B vitamins.
Here are three top-rated fish oil and B vitamins options based on purity, potency, and third-party testing.
This is one of the most recommended fish oil supplements by healthcare professionals.
It contains high levels of EPA and DHA, over 1000mg per serving, and is sourced from wild-caught, sustainably harvested fish.
It’s also third-party tested for purity and freshness, ensuring no heavy metals or rancidity.
A liquid option for those who prefer to avoid softgels. It delivers 1600 mg of omega-3s per teaspoon and has a clean lemon flavour to eliminate fishy aftertaste.
It’s also certified by IFOS (International Fish Oil Standards) for safety and quality.
Each serving provides 2200 mg of fish oil, including 1400mg of EPA and 480mg of DHA.
It’s a great budget-friendly option that doesn’t compromise potency or purity. Enteric-coated softgels help prevent fishy burps.
This whole-food, organic B-complex is made from fermented, plant-based ingredients and includes gut-support probiotics.
It’s ideal for those seeking a more natural option without synthetic fillers or binders.
Thorne is known for pharmaceutical-grade supplements, and this B-complex is no exception.
It includes activated forms of B2, B6, B12, and folate (as methylfolate) for superior absorption, making it especially suitable for individuals with MTHFR gene mutations.
This widely available and budget-friendly option covers all eight B vitamins with added Vitamin C.
It’s USP verified for potency and purity, ensuring you get what’s on the label without contaminants.
B vitamins are directly involved in energy metabolism, converting nutrients into usable energy. While fish oil supports overall health, it doesn’t directly affect energy production. Therefore, B vitamins are more effective for boosting energy levels.
Taking fish oil and B vitamins together is safe and may offer synergistic benefits, particularly for brain and heart health. Combining these supplements can enhance cognitive function and reduce cardiovascular risk factors.
Vegans can benefit from omega-3 supplements, but since fish oil is derived from animal sources, algae-based omega-3 supplements are a suitable plant-based alternative, providing essential EPA and DHA.
If you’re struggling with low energy, mood swings, or brain fog, a B-complex supplement could help restore mental clarity and drive. On the other hand, if your goals revolve around reducing inflammation, protecting your heart, or supporting your joints and brain as you age, fish oil is a wise choice.
For many people, especially those dealing with stress, ageing, or menopause-related symptoms, the combination of fish oil and B vitamins offers a robust, research-backed strategy for feeling better both mentally and physically. As always, speak with your healthcare provider before adding new supplements to your routine, especially if you’re taking medications or managing chronic health conditions.
medically reviewed by margaret etudo, BPharm. written by the vitamins for woman team.