Some of the most exciting highlights of the research from this past year:

• Researchers found that a Western diet (lots of junk food) actually shrinks the hippocampus, a brain structure involved in mood regulation (1)
• Data from the Women’s Health Initiative study found that a high-glycemic index diet (that is, lots of sugars and white flour products) increases the risk of depression (2)
• Cocoa and chocolate are rich in flavonoids that improve cardiovascular health – and now have been found also to improve cognitive function (thinking) (3)
• A whole foods-based diet, especially one following the Mediterranean pattern, is associated with improvement in depression and anxiety (4)
• A placebo-controlled study found that a specific probiotic supplement (Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium bifidum) significantly improved symptoms of depression, along with metabolic health markers like C-reactive protein (hsCRP). (5) This builds on previous evidence showing decreased moodiness with probiotic intake.

In addition to a whole foods-based diet and probiotics, don’t forget that exercise is one of the most powerful natural antidepressants there is. If additional mood support is needed, there are many powerful herbs and nutrients that can help – just be sure to use them with appropriate guidance, since some (like St. John’s wort) can have significant interactions with drugs.

1. Jacka FN, Cherbuin N, Anstey KJ, Sachdev P, Butterworth P. Western diet is associated with a smaller hippocampus: a longitudinal investigation. BMC Med. 2015;13:215.
2. Gangwisch JE, Hale L, Garcia L, et al. High glycemic index as a risk factor for depression: analyses from the Women’s Health Initiative. Am J Clin Nutr. 2015;102:454-463.
3. Mastroiacovo D, Kwik-Uribe C, Grassi D, et al. Cocoa flavanol consumption improves cognitive function, blood pressure control, and metabolic profile in elderly subjects: the Cocoa, Cognition, and Aging (CoCoA) Study—a randomized controlled trial. Am J Clin Nutr. 2015;101:538-548.
4. Agarwal U, Mishra S, Xu J, Levin S, Gonzales J, Barnard ND. A multicenter randomized controlled trial of a nutrition intervention program in a multiethnic adult population in the corporate setting reduces depression and anxiety and improves quality of life: the GEICO study. Am J Health Promot. 2015;29:245-254.
5. Akkasheh G, Kashani-Poor Z, Tajabadi-Ebrahimi M, et al. Clinical and metabolic response to probiotic administration in patients with major depressive disorder: a randomized, double-blind, placebo-controlled trial. Nutrition. 2015 Sept 28. [Epub ahead of print]

For this reason, antidepressants have become one of the most widely prescribed classes of drugs in the US over the last 20 years.  The most common of these are the SSRIs, such as Prozac (fluoxetine).  While these medications can help people to live more normal and productive lives, they do come with significant side effects, such as sleep disturbances, loss of libido, weight gain, and even an increase in suicidal ideation.

There is good research about natural alternatives for mild to moderate depression, such as aerobic exercise and St. John’s wort.  Exciting new research out of India has highlighted a safe alternative for major depression: curcumin.  Curcumin is the active compound in the herb turmeric.  This was a relatively small study, involving 60 patients with major depressive disorder.  They were divided into three groups: one group received fluoxetine, 20 mg daily; the second group received curcumin, 1000 mg daily; the third group received a combination of the two.  Outcomes were measured using the Hamilton Depression rating scale.  There was no statistical difference in the response rate among the three groups, and at the end of six weeks, the change in Hamilton score was comparable in all three groups.

This is big news.  Depression is a serious health condition, but the side effects of SSRIs are further complicated by the difficulty that patients have in coming off these medications.  On the contrary, the “side effects” of curcumin include:

• protection against neurodegenerative diseases such as Parkinson’s and Alzheimer’s,
• enhanced gastrointestinal health,
• protection of the liver against toxins,
• anti-inflammatory effects from muscles and joints,
• and more.  

One thing to keep in mind about curcumin, however, is that most standardized extracts are poorly absorbed from the intestinal tract.  It is best to use curcumin that is complexed with phosphatidylcholine (such as Curamin [BCM-95–the type used in this study] or Meriva), or used in conjunction with black pepper (piperine).

A last note of caution: if you are currently taking antidepressant medications, do not discontinue them abruptly.  Consult with your prescribing physician about weaning down gradually on the dosage, to avoid withdrawal effects.  It is perfectly safe, however, to start taking curcumin while still on the pharmaceutical antidepressant.

1.  Efficacy and Safety of Curcumin in Major Depressive Disorder: A Randomized Controlled Trial.  Phytother Res. 2013 Jul 6. doi: 10.1002/ptr.5025. [Epub ahead of print]

When you count the microorganisms living in your gastrointestinal tract, skin, and respiratory tract will, there are ten times as many bacterial cells as human cells in your body.  We are ecosystems, rather than single organisms.  If 20th century nutrition was the discovery of vitamins, proteins, carbohydrates, and other nutrients, 21st century nutrition will be the study of how nutrients affect those 90% of nonhuman cells within us.

These friendly bacteria (also known as normal flora or probiotics) play an important role in our gastrointestinal health, allergies, normal immune system functioning, and maintaining a normal body weight.  Some intriguing early animal studies found that probiotics could even decrease symptoms of depression.  In the June issue of the journal Gastroenterology, researchers at UCLA published the first study showing a direct effect of probiotics on the human brain.  And no, this does not mean that people were shoving yogurt into their ears.

Researchers divided a group of 36 healthy women into three subgroups: the first received two servings of yogurt with probiotics daily; the second subgroup received non-fermented milk products; and the third subgroup received no special foods.

After four weeks, these women underwent psychological testing while in a functional MRI (fMRI) — an imager that examines real-time brain activity, rather than just taking a static image.  The probiotic subgroup showed significantly reduced activity in brain areas associated with emotional variability and pain.  Translation?  Probiotics made them less moody!

The importance of this study is that it proves that gut bacteria can have a direct impact on human brain functioning, specifically in the areas of emotions and pain perception.  It did not examine what the exact mechanism of action is.  We also have to be a bit cautious with this study, because these were healthy volunteers, with no gastrointestinal or psychological disorders.

Nevertheless, this just adds another piece of evidence that indicates that tending to the complex “rain forest” within us, with fermented foods and lots of dietary fiber, is probably more important than taking high doses of any single nutrient.

Tillisch K et al.  Consumption of Fermented Milk Product With Probiotic Modulates Brain Activity.  Gastroenterology June 2013; 144(7):1394-1401.

In the 1980s, a medical doctor by the name of William Crook published a book called The Yeast Connection.  The gist of it is that many symptoms of fatigue, joint pain, depression, etc., are the result of by-products of yeast overgrowth in the body.  Eating a diet that starves the yeast (eliminating sugar and refined grains) can therefore resolve these symptoms.  Sometimes anti-yeast medications may be required also.

Is yeast real?  Of course — Candida albicans, the main yeast species that Dr. Crook refers to, is part of the normal flora of our intestinal tract in small amounts.  When there is an overgrowth of candida, it can cause gastrointestinal (GI) bloating, indigestion, and constipation or diarrhea.  Overgrowth in the genital tract cause those annoying vaginal yeast infections; candida from the GI tract can serve as a reservoir for recurring infection.  And indeed, waste products produced by candida in the GI tract can be absorbed and cause more widespread symptoms in the body.

So why am I calling this a myth?  The problem is with misperceptions surrounding candida:

1. You can diagnose candida overgrowth from a symptom questionnaire.  There are many, many problems in the body that can lead to fatigue, joint pain, etc.  Doing a stool test to check for yeast, or a urinary organic acid test to check for yeast by-products, are the only ways to know for sure that intestinal candida is the culprit.  In that case, specific anti-yeast therapies (pharmaceutical or natural) may be needed.  However, doing a “cleanse” for candida or parasites without evidence is most likely a waste of effort.
2. “Whole-body candida.”  Some folks get the impression that candida is growing throughout the bloodstream or other parts of the body, besides the GI or genital tracts.  This only occurs in severely immunocompromised conditions, such as AIDS.  The by-products from yeast might be high in the bloodstream, but not the organisms themselves.
3. You need to avoid all yeast and mushrooms on an anti-candida diet.  Candida is part of the fungus kingdom — a completely separate branch of life from plants, animals, and bacteria.  However, it is only one species.  Baker’s yeast is a completely different species (Saccharomyces cerevisiae), and mushrooms are of many other different species.  Avoidance of everything in the fungus kingdom is akin to saying that because you are allergic to cats, you need to avoid elephants, trout, ladybugs, bald eagles, and everything else in the animal kingdom.  One particular yeast — Saccharomyces boulardii — is even considered a powerful probiotic (beneficial organism) that helps boost our immune response (1,2). 
4. You need to kill all candida in the body in order to be cured.  This is a well-nigh impossible task.  All of us have some candida in the GI tract, along with hundreds of other species of microorganisms.  Our normal flora is more like a complex rainforest ecosystem, rather than the one or two species present in a probiotic supplement.  The key is in the balance, and making sure that there isn’t overgrowth of candida.

Yes, the weather is still blazing summer heat (though we’ve finally been getting a break now and then!), but we hit a transition in the last couple of weeks.  Somewhere in there, we reached the point where it’s still dark outside when my 5:30am alarm goes off.  There’s about a three-month period — six weeks on either side of the summer solstice — when I get to awake to glorious dawn light.  It’s a natural part of our physiology:  It’s much easier to get up and get started on the day that way, than to feel like my alarm is going off in nighttime darkness.

So this is my reminder that we’re starting on the back half of the year, approaching autumn, sliding gradually toward the winter solstice, the days becoming shorter and shorter.  We’re even getting back into the school year routine.

As we approach this transition, it’s a good time to reflect on our health habits.

• I get energized in the early morning darkness with a contrast shower (most important as the weather gets cooler).  
• Take an inventory of your eating habits:  Did you take advantage of the abundant fresh fruits of summer, or use the hot weather as an excuse to indulge in too much ice cream, barbecue, and diet soda?  Reorient your thinking to the rich fall harvest of healthy veggies and lean meats.  
• As the days get shorter, it’s also a time to think about getting your blood levels of vitamin D tested, since low levels of this “sunshine vitamin” have been associated with cardiovascular disease, autoimmune disease, seasonal affective disorder, and polycystic ovarian syndrome, to name a few.  
• And if the summer led to relaxation of your exercise routine, time to get back into some physical activity, since it’s so critical to your health.

Melatonin is produced by a tiny gland at the base of the brain called the pineal gland.  The pineal gland releases melatonin in response to darkness, and this signals the brain to go into sleep mode.

Recent findings have shed more light (so to speak) on the importance of darkness and melatonin.  Melatonin has antioxidant effects in the body that protect against cancer.  Nurses who work the night shift (and therefore get round-the-clock light exposure) produce less melatonin, and are at significantly higher risk for breast cancer (1, 2).

A new study found that even low light levels in the sleeping room at night can produce symptoms of depression (3).  Granted, this study was done using hamsters, but the biological effects were clear:  depressive symptoms after four weeks of dim light at night.

Depression?  Insomnia?  Cancer risk?  Turn out the lights:  shut off all screens (TV, computer, iPad, smartphone, etc.) 30-60 minutes before bedtime.  Get rid of the night lights and television in the bedroom.  You might even want to move that bright LED alarm clock away from your head.  Allow a few weeks for your body to readjust to what is becoming a scarce, but highly valuable, commodity:  darkness.

1. Cancer Epidemiol Biomarkers Prev. 2012 Apr;21(4):609-18. Epub 2012 Feb 7.
2. Cancer Causes Control. 2006 May;17(4):539-45.
3. T A Bedrosian, Z M Weil and R J Nelson.  Chronic dim light at night provokes reversible depression-like phenotype: possible role for TNF.  
   Molecular Psychiatry , (24 July 2012).