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Several clear trends defined studies on supplements this past year. For starters, health experts around the world began talking more about the “human microbiome” and the role that gut bacteria and probiotics play in supporting health. Also popular this year: research continued to affirm the health benefits of vitamin D3 supplements. There was also a focus on the need for further research into certain bestselling natural products, namely fish oils and glucosamine and chondroitin.
Here’s a look back at a few of the best clinical studies in nutritional medicine from 2015.
Improving ADHD and Autism with Probiotics
Gastrointestinal (GI) disturbances are common in children with attention deficit hyperactivity disorder (ADHD) and autism spectrum disorders, including Asperger’s syndrome. One theory is that lower levels of beneficial gut bacteria such as Lactobacillus and Bifidobacteria lead to an increase in toxin-producing bacteria such as Clostridium. An altered gut flora also contributes to increased gut permeability, causing the body to absorb toxins and partially digested bits of food, which are not normal processes. This alters the body’s immune responses, potentially affecting brain cells.
To test the theory, researchers in Finland recruited 159 expectant mothers and gave them 1 billion colony-forming units (CFUs) of Lactobacillus rhamnosus or a placebo daily for four weeks before delivery. After the babies were born, the probiotic (or the placebo) was given to the children or the mothers (if breast-feeding) for 6 months. Results showed that ADHD or autism was diagnosed in 17 percent of the children in the placebo group, whereas none of those in the probiotic group developed either condition.
The researchers concluded, “Probiotic supplementation early in life may reduce the risk of neuropsychiatric disorder development later in childhood.”
Women taking a probiotic supplement lost twice as much weight as those in a placebo group, according to a recent study.
Boosting Weight Loss with Good Bacteria
The link between gut flora and obesity was first discovered by comparing intestinal bacteria in obese and lean individuals. That led to mice studies in which the bacterial flora from the colons of fat mice were switched with flora from skinny mice. When the skinny mice were inoculated with flora from fat mice, they became fat and vice versa.
In a recent double-blind, placebo-controlled trial from Montreal, 125 overweight men and women followed a 12-week weight-loss plan, followed by 12 weeks of maintaining their weight loss. Throughout the study, half of participants took 2 capsules daily of Lactobacillus rhamnosus with 3.2 billion CFUs; the other half were given a placebo.
After the 12-week diet portion of the study, the women in the probiotic group experienced an average weight loss of 4.4 kg; women in the placebo group lost 2.6 kg. And after the maintenance period, the weight of women in the placebo group remained stable, whereas the probiotic group continued to lose weight at an average of 5.2 kg per person.
Essentially, the women taking the probiotic lost twice as much weight over a 24-week period as women taking a placebo. Interestingly, no differences in weight loss were observed among the men in the two groups.
Lifting Depression in College Students with D3 & Fish Oils
According to recent surveys, 30 percent of undergraduate students feel so depressed that it hinders their ability to function, and 6 percent seriously consider suicide. New research from Oregon State University showed that low blood levels of vitamin D are associated with symptoms of depression in otherwise healthy female undergraduates.
Meanwhile, researchers at the University of Pittsburgh evaluated the effects of fish oil supplementation on depression in undergraduates, 78 percent of whom were female. Subjects were randomly assigned to a placebo or fish oil group (1.4 g daily of EPA and DHA). There was a significant difference in levels of between the two groups. Out of the students taking fish oils, 67 percent no longer met criteria for depression, while only 20 percent in the placebo no longer felt depressed. These results are significant-they show that fish oils can boost mood quickly.
Easing Arthritis Pain with Glucosamine and Chondroitin
A new study published in the Annals of the Rheumatic Diseases showed that glucosamine and chondroitin sulfate decreased pain scores in people with osteoarthritis of the knee comparable to those seen in patients taking Celebrex, a prescription pain reliever.
These results provide further evidence that glucosamine and chondroitin products are effective in improving the underlying factors that lead to arthritis pain, as the duo have no direct pain-relieving action.
The dosage used in the trial was 400 mg of chondroitin sulfate and 500 mg glucosamine hydrochloride per capsule. It’s also important to note that glucosamine and chondroitin are not associated with side effects.
Vitamin K2 may help improve one of the most debilitating inflammatory conditions- rheumatoid arthritis.
Treating Rheumatoid Arthritis with Vitamin K2
Just as there has been an explosion of positive science on the importance of vitamin D3, vitamin K2 is now gaining similar recognition in the treatment and prevention of a range of health conditions. A new study published in the European Journal of Pharmacology details how this underutilized form of vitamin K (K2) may help improve one of most debilitating inflammatory conditions-rheumatoid arthritis (RA).
In the study, 84 patients with RA were divided into treatment and control groups. Researchers used a proprietary form of vitamin K2, know as MK-7, giving 100 mcg daily for three months to patients in the treatment group. Subjects continued on their prescription medications for RA.
The results showed a statistically significant decrease in several markers of inflammation in the MK-7 group.
MK-7 was also shown to boost patients’ levels of the active form of osteocalcin, an indicator of healthy bones.