STUDY: Effects of an exercise intervention on depressive symptoms and sleep quality

In this small, 12-week, randomised controlled trial, women with obesity and living in a low socioeconomic community were allocated into an exercise or control group. The exercise intervention involved 40 to 60 minutes (4-days a week) of combined resistance and aerobic training, while the control group maintained their habitual diet and activity. At the end of 12-weeks, the exercise group experienced a significantly greater reduction in depressive symptoms, and improved sleep quality and sleep efficiency. A reduction in depressive symptoms was associated with an improved peak oxygen consumption (a measure of cardiorespiratory fitness), while a reduction in sedentary activity was associated with better sleep quality.

REVIEW ARTICLE: The Efficacy of Probiotics on Depression, Inflammation, and Oxidative Stress

Based on the results from twelve studies and 650 participants, it was concluded in this meta-analysis that probiotic supplementation for 6 to 12 weeks is associated with a reduction in depressive symptoms (based on the Hamilton Depression Rating Scale), a reduction in C-reactive protein and interleukin-10 (markers of inflammation), and a reduction in malondialdehyde concentrations (a marker of oxidative stress/ free radical damage). These studies were conducted on adults with depression, schizophrenia, and Alzheimer’s disease. These results are promising although we need to still find out the most effective mood-enhancing probiotic strains, dosages, and treatment duration.

REVIEW ARTICLE: Association of Anxiety and Depression in Obstructive Sleep Apnea Patients: A Systematic Review and Meta-Analysis

Obstructive sleep apnoea (OSA) is a sleep disorder where people stop breathing during the night. Based on the results from 73 articles, it was confirmed that in people with OSA, 35% suffered from depressive and 32% from anxiety symptoms. This rate is far higher than that seen in the general population. It is believed that there is a bi-directional relationship between OSA and mental health symptoms. That is, OSA increases depression and anxiety symptoms, and depression/anxiety symptoms increase the likelihood of OSA (possibly due to its association with high stress and unhealthier dietary and lifestyle factors). If you experience depression and anxiety be sure to rule out OSA as a potential contributory factor. Risks factors and symptoms for OSA include snoring, stop breathing during the night, obesity, high blood pressure, tiredness, over the age of 50yrs, and male.

REVIEW ARTICLE: The role of physical activity in reducing neuropsychiatric symptoms in Alzheimer's disease

In this review, it was concluded that even though there are some contradictory results, most studies found physical activity had a significant effect on depression and sleep disturbances in patients with Alzheimer’s disease. Physical activity may be beneficial due to its ability to modulate neurotransmitter production, increase neurotrophins, reduce oxidative stress, lower inflammation, increase cerebral blood flow, regulate the activity of the hypothalamic pituitary adrenal axis, and support neurogenesis and synaptogenesis. These results suggest that physical activity should be part of an integrative treatment for neuropsychiatric symptoms associated with Alzheimer’s disease. 

REVIEW ARTICLE: The association between loneliness, social isolation and inflammation: A systematic review and meta-analysis. 

Chronic inflammation is associated with most mental and physical conditions. Lifestyle and environmental causes of inflammation include a poor diet, physical inactivity, poor sleep patterns, and stress. In this meta-analysis, it was confirmed that loneliness and social isolation may be another cause of inflammation. Based on the results from 30 studies, loneliness and social isolation were associated with several inflammatory blood markers such as C-reactive protein and interleukin-6. The authors concluded that the results indicate that social isolation and loneliness could be linked with systemic inflammation, but more robust studies are needed to understand these associations. Overall, this study indicates that along with eating a healthy diet, getting good sleep, being physically active, and consuming anti-inflammatory herbs and spices, ensuring good social connections is another way to reduce chronic inflammation.

REVIEW ARTICLE: Beneficial Effects of Walnuts on Cognition and Brain Health.

Oxidative stress and neuroinflammation are associated with ageing, cognitive impairment, and Alzheimer’s disease. In this review paper, the authors report that walnuts contain several components that have antioxidant and anti-inflammatory effects. Moreover, animal and human studies have suggested that supplementation with walnuts in the diet may improve cognition and reduce the risk and/or progression of mild cognitive impairment and Alzheimer’s disease. The authors suggest that early and long-term dietary supplementation with walnuts may help to maintain cognitive functions and may reduce the risk of developing or delaying the onset and/or slowing the progression of mild cognitive impairment and dementia. Walnuts do this by decreasing amyloid beta protein fibrillization, reducing oxidative damage, increasing antioxidant defence, and decreasing neuroinflammation.

STUDY: Anti-anxiety effects of ashwagandha

Ashwagandha is an Ayurvedic herb that has been traditionally used to reduce stress and enhance general wellbeing. In this eight-week, randomised, double-blind, placebo-controlled study, 60 adults experiencing high stress received either (1) a placebo, (2) 250mg daily of an Ashwagandha extract (KSM-66), or (3) 600 mg of KSM-66. Compared to the placebo, Ashwagandha (at both doses) was associated with greater reductions in stress, and improvements in sleep quality. However, it seemed the higher dose was more effective. Levels of serum cortisol (a marker of stress levels) were also significantly reduced in people taking ashwagandha.

STUDY: The sleep-enhancing effects of saffron

We have just published in the Journal of Clinical Sleep Medicine the results of our study examining the sleep-enhancing effects of a saffron extract (affron®). In this randomised, double-blind, placebo-controlled study, 63 adults with self-reported sleep problems took either affron® (14mg, twice daily) or a placebo for 28-days. Compared to the placebo, saffron intake was associated with greater improvements in overall sleep quality and reports of refreshing sleep. The good news is most of the improvements occurred after 7-days of treatment with continued, albeit less dramatic improvements thereafter.

STUDY: Leaky gut and brain barrier found in bipolar disorder

Zonulin is a biomarker for intestinal permeability and claudin-5 is an important part of the permeability of the blood brain barrier. In this study, the researchers compared levels of serum zonulin and claudin-5 in adults with bipolar disorder to healthy controls. Levels of zonulin and claudin-5 were significantly higher in patients with bipolar disorder. This suggests that in adults with bipolar disorder, disturbances in both the intestinal barrier and blood-brain barrier could contribute to the onset or progression of the disease. This is exciting news as treatments to restore both the gut and brain barrier may lead to symptom remission in people with bipolar disorder. As is often the case, more research is required.

STUDY: Hair cortisol and depressive symptoms in youth

Hair cortisol is becoming increasingly recognised as a useful biomarker of stress. In this study, the relationship between hair cortisol and depressive symptoms was examined in 432 adolescents aged 11 to 17 years. Unlike blood and saliva measures of cortisol (which provide an acute measure of cortisol/stress), hair cortisol provides a chronic measure of cortisol output over the last 3 months. The researchers found that both high and low hair cortisol was associated with depressive symptoms. It seems that cortisol output needs to be just right. Not too high, or too low. This suggests that hypo- and hyper-activity in our stress response (i.e., the HPA axis) can increase the likelihood of depression.

STUDY: The association between a low carbohydrate diet, sleep status, depression, anxiety and stress

Based on data collected from 265 women with type 2 diabetes, researchers found that compared to people eating a high carbohydrate diet, people consuming a diet low in carbohydrates had a 69% lower risk of poor sleep, 42% lower risk of depression, and 73% lower risk of anxiety. Even though association does not mean causation, it does highlight the need to look further into dietary interventions for sleep and affective disorders. It would also be interesting to specifically look at the relationship in non-diabetics, and the differing effects of eating a diet high in refined carbohydrates compared to the generally healthier complex carbohydrates (e.g., vegetables and whole grains).

STUDY: Higher dietary intake of flavonols associated with a reduced risk of Alzheimer's disease

921 participants with a mean age of 81 years underwent annual neurologic evaluations and dietary assessments using a validated food frequency questionnaire. Initially, none of these participants had dementia. However, 220 of them eventually developed dementia over the average 6 year screening period. The researchers found that a higher dietary intake of flavonols (present in a wide variety of fruits and vegetables) was associated with a lower incidence of Alzheimer's disease (after controlling for age, sex, education, APOE ɛ4 gene, and participation in cognitive and physical activities). When comparing people with the highest versus lowest intake of different flavonols, there was a 38 to 51% decreased risk of developing Alzheimer's disease. Beats any drug!

STUDY: Neuroprotective effects of ashwagandha in hypothyroidism

In this animal study, hypothyroidism was induced in rats after the administration of the anti-thyroid drug propylthiouracil (PTU). PTU administration not only induced hypothyroidism but also increased oxidative stress and brain inflammation (cortical and hippocampal regions). When rats were given thyroxine or the Indian herb ashwagandha, levels of the thyroid hormones T3 and T4 were restored. In the hippocampus, thyroxine prevented increases in oxidative stress induced by PTU but had no effect on brain inflammation. However, ashwagandha had a positive effect on both oxidative stress and inflammation in the hippocampus. The researchers concluded that ashwagandha could prevent thyroid dysfunction and reduce its complications on the nervous system including oxidative stress and neuroinflammation.

STUDY: A high-refined carbohydrate diet induces anxiety-like behaviours

In this study, the researchers evaluated whether consumption of a high-refined carbohydrate-containing diet (HC) could induce anxiety-like behaviour in mice. Mice were fed a standard diet or a HC diet for 3 days or 12 weeks. The chronic (12-week) consumption of a HC diet, but not the acute 3-day intake, induced anxiety-like behaviours in the mice. The chronic intake of a HC was also associated with increased inflammation in different parts of the brain known to be associated with anxiety (i.e., hippocampus and prefrontal cortex). This animal study provides further support of the important link between diet and mental health.

STUDY: The different effects of exercise intensity on the brain

In this study, the effect of exercise intensity on different brain regions in male athletes was investigated. Resting-state functional magnetic resonance imaging (MRI) was used to examine the effects of a 30min low or high-intensity bout of exercise on the brain. Even though positive mood improved after both exercise conditions, low-intensity exercise had a larger effect on brain networks associated with cognition and attention (the frontoparietal network), while high-intensity exercise had a greater effect on brain networks involved in affective/emotion processing (left affective and reward network). These results suggest that low-intensity exercise may be more helpful for cognition and attention, whereas high-intensity exercise may have a greater influence on mood.

STUDY: Saffron, a potential natural pain-reliever

Calcitonin-gene related peptide (CGRP) is a protein in the body believed to be associated with pain perception. Higher levels are found in people with joint and muscular pain, and migraine. Saffron has been shown to have positive anti-depressant and anxiolytic effects. In this animal study, crocin (a component found in saffron), reduced levels of CGRP. In addition to its mood-lifting effects, saffron may, therefore, have pain-relieving effects and could be helpful for people with pain-related conditions and/or people with comorbid depression and physical pain. However, human studies are required.

STUDY: The importance of the blood-brain barrier in depression

In this paper, the researchers argue that to treat depression more effectively, restoration of the blood-brain barrier (BBB) is important. Chronic social stress alters the integrity of the BBB through the loss of the tight junction protein claudin-5. Interestingly, in animal and in vitro studies, high glucose levels and a high-fat diet can have a negative effect on claudin-5. However, in some studies, it has been shown that curcumin and exercise can restore claudin-5 levels and potentially improve BBB integrity. This is another reason why we should consider diet, herbs, and lifestyle factors as an intervention for depression.

STUDY: Whole-body cryotherapy. A promising add-on treatment for depression

This is an interesting study on the use of cryotherapy for the treatment of depression. The treatment involves entering a cryotherapy chamber at -110 to -135 degrees celsius for 2 minutes. Ten sessions over 2 weeks were associated with significant reductions in depression in adults suffering from long-standing depression. It is believed that cryotherapy may have anti-inflammatory effects, which could be the reason for its mood-lifting effects. This was a small, open-label study so more research needs to be undertaken. But it is very interesting.

REVIEW: The effects of saffron on blood glucose and lipid profiles

In this systematic review of six studies, it was concluded that saffron supplementation was associated with reductions in triglycerides and total cholesterol, and an increase in high-density lipoprotein cholesterol. Therefore, in addition to its positive effects on depression, saffron has the potential to have positive effects on cholesterol metabolism and the prevention/treatment of heart disease.

REVIEW: Serum uric acid as a predictor of bipolar disorder in people with depression

In this study, levels of uric acid significantly predicted which depressed adults would go on to develop bipolar disorder. That is, the higher the uric acid level, the greater the likelihood of developing bipolar disorder. This finding has now been replicated in several studies. Allopurinol is a xanthine oxidase inhibitor used to lower uric acid and has been shown to be an effective add-on medication for the treatment of mania. Many plant compounds are also natural xanthine oxidase inhibitors (e.g., quercetin). The relationship between uric acid and mania requires more research as it potentially provides a new treatment avenue for bipolar disorder (particularly mania).

STUDY: The relationship between vitamin D and premenstrual symptoms

In this study of almost 1000 women aged 20 to 29 years, low vitamin D levels were associated with the following premenstrual symptoms: increased confusion, desire to be alone, cramps, anxiety, and reduced sexual desire. While correlation does not mean causation, it may be useful for women experiencing premenstrual symptoms to have their vitamin D levels tested.

STUDY: Music therapy as a treatment for for dementia

It was confirmed in this meta-analysis of 38 trials and 1400 participants with dementia (aged 75 to 90 years) that listening to music could reduce agitation, behavioural problems, and anxiety in older people with dementia. A simple and free intervention to enhance one's quality of life!

STUDY: The effect of mother's diet on ADHD trajectory in children

In this study, the relationship between a mother’s diet during pregnancy and children’s ADHD symptoms was investigated. Data was collected from 1,242 mother-child pairs from pregnancy until children were 8 years of age. The results showed eating a 'low Healthy diet' or a 'high Western diet' during pregnancy was associated with a 60% increased odds of a child exhibiting high ADHD symptoms.