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Yes, Where Do I Start?

Natural Mood Enhancers: How to Improve Depression and Anxiety Without Medication

Key Takeaways:
  • An anti-inflammatory diet, coupled with probiotics, improves gut bacteria, which in turn can balance brain chemicals and act as a natural mood enhancer.
  • Gut-healing treatments can help address the root cause of mood issues, giving them an advantage over other therapies, while also remaining safe to use alongside antidepressants/anti-anxiety meds.
  • Mindfulness-focused cognitive behavioral therapies are useful alongside improving gut health for depression.
  • You can also try St. John’s Wort (a mild, herbal version of an SSRI antidepressant) for depression symptoms.
  • Other natural mood boost supplements include fish oils, saffron, and S-adenosyl-l-methionine (SAMe).
  • Natural supplements are gentler and generally better tolerated than antidepressant drugs, but they may not work or be safe for everybody — especially those taking certain antidepressant medications.
  • There are also mood-boosting benefits to exercising in nature, getting vitamin D from safe sun exposure, and sitting in saunas.

It’s natural that life’s challenges can sometimes make us feel down or create anxious feelings. Most times we will bounce back relatively easily, but when overcoming uncomfortable emotions gets a little harder, it’s good to know that there are a range of natural mood enhancers that can help.

Of course, there’s a time and place for pharmaceutical antidepressants, but they aren’t for everyone, and there can be issues with these medications, such as side effects, poor efficacy for some users, and the fact that they may not address the underlying causes of depression [1, 2, 3].

When I talk to my patients with mental health issues, most of them want to try a more natural approach, especially when I explain that symptoms of depression and anxiety can often be related to solvable gut health issues.

When patients realize they can improve their mood with diet and lifestyle changes, supported by certain natural remedies, it can be very empowering.

Some popular natural mood enhancers that come in supplement form (and which we’ll go into more detail on below), include:

  • Probiotics
  • St. John’s Wort
  • Fish oils
  • S-adenosyl-l-methionine (SAMe)
  • Saffron

However, I don’t recommend these natural mood enhancers as your first line of action. It’s better to start with diet and lifestyle changes that more fundamentally underpin good mental health.

And of course, if you’re taking prescription medication for depression or anxiety, never stop or lower the dose without first speaking with your physician.

The Gut /Mood Connection

Several research reviews have shown that depression is more common in people with gut issues, e.g. irritable bowel syndrome (IBS), and nutrient deficiencies [4, 5].

Depression also regularly occurs with chronic inflammatory illnesses [6], which include inflammatory bowel disease (IBD), cancer, and heart disease [7].

Anxiety is another mental health issue that commonly co-exists with gastrointestinal disorders — for example, if you have IBS, IBD, or celiac disease you are likely to experience anxiety more often than if you didn’t have these conditions [8, 9, 10, 11].

Anxiety can in turn increase your perception of chronic health symptoms, including gut symptoms.

The common factor that may link poor gut health, inflammation, and mental health is gut dysbiosis, or disruption to the bacteria, yeast, and other microorganisms that live in our digestive tract (collectively known as our gut microbiota). A 2020 literature review found that compared to healthy people, those with depression have a greater chance of an unbalanced gut microbiota (gut dysbiosis) [12].

It’s not fully understood how gut microbiota /brain communication works, but one important aspect appears to be that gut bacteria modulate the activity of the vagus nerve. This nerve passes signals between the gut and brain, and is an important constituent of the parasympathetic nervous system, which helps regulate immune response, digestion, and heart rate, as well as mood [13, 14]. 

Gut bacteria also directly produce neurotransmitters (substances that transmit messages from nerve cell to nerve cell) including serotonin, dopamine, and gamma-aminobutyric acid (GABA) [14, 15, 16, 17]. This is why the gut is sometimes called the “second brain”. 

When poor gut health creates dysbiosis and inflammation, the normal messaging that occurs between the gut microbes and the brain can get disrupted, potentially giving rise to anxiety and depression.

A Gut Healthy Diet is Key to Balancing Mood

Fortunately, it’s relatively easy to make beneficial changes to your gut health and the health of your microbiota by making changes to what you eat. In turn, your brain health may receive a boost. These multi-system benefits are why an anti-inflammatory diet is one of the best holistic and natural mood enhancers.

Many observational studies have found an anti-inflammatory diet, the most studied of which is the Mediterranean diet, is associated with less depression and also with increasing gut bacteria diversity (a sign of a healthy microbiome) [18].

For example:

  • In a randomized controlled trial study that compared the effect of a Mediterranean-style diet with extra fish oils, versus psychosocial therapy in depressed people, the Mediterranean diet group had a greater reduction in depression and better mental health quality of life scores. This occurred after 3 months and still persisted after 6 months.
    • Food and nutrient patterns especially associated with better mental health included nuts, a diverse range of vegetables, legumes, and omega-3 fatty acids [19].
  • In another research paper, this time a 2019 meta-analysis of 41 observational studies (more than 300,000 participants) the Mediterranean diet was associated with a 33% lower risk of depression. Diets with a lower inflammatory index were associated with a 24% lower risk of depression [20].
  • In a 2022 meta-analysis, rates of anxiety were 80% higher in women eating a highly inflammatory diet compared with a low-inflammation one. In men, the figure was 47% [21].

The bottom line seems to be that a Mediterranean diet, with its focus on anti-inflammatory foods, such as antioxidant-rich vegetables and oily fish, seems particularly suited to boosting mood. But it’s likely that any anti-inflammatory type diet will be helpful, so you should choose one that fits best with your dietary needs and sensitivities.

In my clinical work with patients I’ve noticed that some people with gut and/or mental health symptoms may have more dietary sensitivities than the general population, in which case a Paleo diet may be a better choice, as it eliminates the most common food sensitivities

Pros and Cons of Fermented Foods

Fermented foods, like kombucha, kefir, and kimchi can help maintain a healthy gut and have been shown, in one meta-analysis, to have a beneficial effect on depression, (probably by modifying gut bacteria, decreasing low-grade inflammation, and influencing the production of neurotransmitters) [22]. 

However, while these foods would normally be a useful part of a gut-healthy diet, there is an important contraindication for people taking prescription MAOI (monoamine oxidase inhibitor) antidepressants. If you are on these antidepressants, fermented foods may increase levels of a chemical called tyramine in the body to dangerous levels, so you should steer clear.

Probiotics Act as Natural Mood Enhancers

With the fundamentals of a gut-healthy, anti-inflammatory diet in place, one of the next options you can consider to protect your mental health is a probiotic supplement. 

Though supplementing with friendly gut bacteria may not be the first thing you think of for mental health, there is actually plenty of evidence that probiotics help lift mood in depressed people. This is likely for the reasons outlined above (i.e. the role a healthy microbiome plays in communication with the brain and vice versa).

Studies looking at the mood-boosting capabilities of probiotics have found that:

  • Depression scale scores for major depressive disorder were improved in people taking probiotics [23].
  • Probiotics had a moderate to large positive impact on people with mild to moderate depression [24].
  • Psychiatric patients who took probiotics had improved scores on the Hamilton Rating Scale for Depression [25].

Some uncertainties still exist around using probiotics for their mood-enhancing qualities. For example, we don’t know if probiotics work for depression by reducing inflammation or not. It’s also unclear whether probiotics can actually prevent depression, or are just useful for treating those already diagnosed with the condition [26]. 

For anxiety, the data is also less clear. For example: 

  • One meta-analysis determined that the evidence for probiotic effects on anxiety wasn’t clear, and more high-quality human clinical trials were needed [27].
  • A second meta-analysis identified possible anti-anxiety effects from probiotics, but found the total sample sizes too small to make clear claims [28].
  • A third meta-analysis found a clear anti-anxiety effect in animal studies, but not enough data in human clinical trials [29].

However, if you currently have a low mood (and particularly if you have coexisting gut symptoms), the evidence for the benefit of probiotics is compelling. They also have many other health benefits and come with a very low risk for side effects. 

In the clinic, I’ve found a good response in depressed and anxious patients from using three different strains of probiotics together.

St. John’s Wort for Depression

St. John’s wort (Hypericum perforatum) is a popular herbal supplement for dealing with depressive symptoms, but you should consult with your doctor before commencing this herb, as it can react with alcohol, other antidepressants, and with many other medications too [30].

Studies suggest St. John’s Wort acts in the same ways as selective serotonin reuptake inhibitor (SSRI) drugs (such as Prozac) for treating mild to moderate depression and anxiety, but people generally tolerate this herbal supplement better than these drugs [31]. 

SSRI medications and St. John’s wort both increase levels of the brain chemical serotonin [30]. As serotonin is broadly associated with being calmer and happier [32], the result can be a lessening of depression and anxiety.

If you decide to give St. John’s worth a go, start by taking one 300mg capsule with 0.3% hypericin content three times a day. 

Other Natural Supplements

In addition to probiotics and St John’s Wort, other dietary supplements with potential mood-enhancing benefits include fish oils, s-adenosyl-l-methionine (SAMe), and saffron.

Fish Oil 

A 2019 practice guideline report by the International Society for Nutritional Psychiatry concluded that fish oil supplements (a rich source of the omega-3 fats EPA and DHA) may be useful for treating major depressive disorder in pregnant women, children, and the elderly, and for preventing it in those at high risk [33]. 

The omega-3 fats (EPA and DHA) in fish oil could have anti-depressant effects by reducing inflammation and improving nerve communication in the brain [33, 34]. 

In one review, high doses of at least 2,000mg/day of combined EPA and DHA had a large positive effect on depression, while lower doses still had a moderate effect [35].

A similar fish oil dosage also had a significant anxiety-lowering effect, both in people with co-existing health issues and those without, according to one pooled analysis of 19 separate studies [36].

Fish oils are largely safe for all groups, including those (like pregnant women) who might not be recommended to take SSRIs, other antidepressants, or certain anxiety medications.


S-adenosyl-l-methionine (SAMe) is made in the body from methionine, an amino acid found in protein.

One theory behind how SAMe exerts its benefits is that it may influence the expression of genes that affect memory, behavior, learning, and cognitive function [37]. It’s thought SAMe may have a role in beating depression by enhancing the activity of certain neurotransmitters (brain chemicals) associated with better mood.

However, the evidence to date doesn’t really support SAMe being more effective than placebo for improving depression when used alone [37]. Instead SAMe seems to be most effective when used as a complementary treatment alongside other antidepressants such as SSRIs. SAMe may make these medications work more effectively as mood enhancers [37, 38].

Use of SAMe is not appropriate with all antidepressants (especially MAOIs), so check with your integrative healthcare provider to see if it is an option for you.


A staple in Indian cooking, saffron (Crocus sativus) also has the benefit of being a mood enhancer when used in concentrated amounts in supplement form.

One meta-analysis suggested saffron could be about as effective as Prozac for treating depression. The quality of the research wasn’t good enough to say this with a high level of confidence though [39].

Nonetheless, saffron has antioxidant, anti-inflammatory, and neuroprotective ingredients, which may all help create a more positive mood [40]. 

A good dosage of saffron for depression appears to be 30–50mg of saffron extract per day, taken for around 6 weeks [39].

Mindfulness-Based CBT for Boosting Mood

MBCT, or mindfulness-based cognitive behavioral therapy, combines elements of mindfulness (to tackle unhelpful/depressive thought patterns) with CBT (to reframe those thoughts and behaviors). 

Two meta-analyses and a randomized controlled trial found that MBCT is as effective as antidepressants for treating recurrent major depression and should be ideally used as a treatment for maintaining mental health after recovering from depression [41].

There’s also good evidence that mindfulness-based CBT can help people with anxiety [42].

MBCT is thought to work as a mood enhancer by teaching you to change your focus, increase the accuracy of memories, reduce the emotional reaction to stress, and have a more accurate sense of self [43].

For people who struggle with insomnia when they are depressed, a specific form of CBT, known as CBT-I (where the “I” stands for insomnia), may also be very effective, as it teaches behaviors that encourage higher quality sleep.

Three different meta-analyses (reviews of many studies) have shown that CBT-I has [44, 45, 46]:

  • A moderate to large positive effect on insomnia 
  • A modest effect on self-reported depression symptoms 

You can learn CBT-I from a therapist in person or online, and you can then apply the therapy yourself at home.

Sunshine, Exercise, and Green Spaces: Nature’s Effective Mood Enhancers

Adding movement and nature to your antidepressant armory can also bring big mood boost benefits.

Most treatment guidelines for depression recommend doing 30–60 minutes of moderate-intensity exercise 2–3 times per week for 9–12 weeks. However, if you can do that exercise outdoors, so much the better.

Benefits of Outside Activity 

Two research reviews that analyzed evidence from many studies to understand the efficacy of nature and activity prescriptions for improving various health measures, found that: 

  • Compared with control conditions, spending time each week in a natural setting, like a park) moderately improved depression scores [47].
  • Compared to walking or running in the urban outdoors, walking in natural outdoors had a small positive effect on depression and moderate to large positive effects on anxiety, energy levels, and vigor [48].

A Sunny Disposition

Being outside when it is sunny, could further boost mood (though it’s important to practice safe UV exposure).

In a 2018 randomized clinical trial, a group of depressed women who were advised on the benefits of daily sun exposure had significant increases in vitamin D, became vitamin D sufficient, and went from being moderately depressed (depression score of about 24) to minimally depressed (depression score of about 13) [49].

Vitamin D from sunlight may potentially help depression by regulating inflammation, or it may just be enjoying a sunny day that boosts mood. Either way, topping up your vitamin D levels provides good general health benefits, and safe sun exposure is good for mental health too. 

It’s important not to burn, however, as this can lead to skin cancers. 

People with darker skin can typically tolerate sunshine on their face, arms, and legs for 25 minutes a day most days before using sunscreen [50]. People with lighter skin can typically tolerate 10–15 minutes a day most days before using sunscreen [51]. This should be sufficient to make enough vitamin D for both groups (lighter-skinned people tend to easily make vitamin D, but they can’t take as much sun without burning and other harmful effects) [50]. 

Taking a vitamin D supplement is a good option if you can’t be out in the sun for any reason, but keep your dose around 2,000 IUs and/or get regular lab work to make sure you aren’t consuming too much.

Relaxing in a Sauna or Hot Bath

Though there isn’t a huge amount of research on the effects of sauna bathing on mood disorders, the practice does appear to have benefits for some people with depression.

One systematic review of seven clinical trials found evidence pointing to a moderate to large positive effect on depressive symptoms after 1–6 weeks. Both infrared saunas (heat delivered to the body by infrared lights) and hot baths were included in this review [52].

Even just one session of whole-body hyperthermia reduced depression for 6 weeks in one study [53]. 

It’s possible that sauna bathing improves the function of cell membranes in the skin, with the downstream effect being improved signaling to serotonin-specific nerve cells, and an improvement in mood [52].

For best effect, you need to raise your core body temperature slightly [52]. This can be uncomfortably hot at first, so take it slowly and check with your doctor if you are unsure [54]. You will also want to be extra careful to stay hydrated if you are taking any prescription antidepressants to avoid fluctuations in blood levels of these medications.

Natural Mood Enhancers Ease Mental Health Symptoms

Severe depression and anxiety may require medical attention and perhaps the use of antidepressant medication, but often you can deal with more mild or moderate symptoms by using natural mood enhancers. And even if you are already on prescription medications for mood, many of these natural remedies can be used to help to treat the cause of your symptoms.

A gut-healthy diet, probiotics, and spending some time being physically active in nature are fundamentals, but beyond that, you may also be able to benefit from a range of natural mood support supplements, such as St. John’s Wort, and fish oils.

However just because they are natural doesn’t make these mood boosters safe for everybody. For example, St John’s Wort acts in a similar way to prescription drugs, and while better tolerated by many, can react with other medications.

The bottom line is to always check with a healthcare professional, particularly before adding natural antidepressant supplements to prescription antidepressants.

If you need more individualized advice on tackling depression and low mood issues, our highly experienced practitioners at the Ruscio Institute are here to help. You can contact us using this link.

The Ruscio Institute has developed a range of high-quality formulations to help our patients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you.

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