The Year in Review
The top herb and supplement studies of 2013
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A growing body of evidence shows that a whole foods-based diet and the use of vitamin and herbal supplements offer significant health benefits-from sharper mental focus to fewer carb cravings. Here’s a closer look at that evidence with some of the most promising nutrition and supplement studies from 2013.

B Vitamins for Better Cognitive Function
Low levels of folic acid, vitamin B6, and vitamin B12 have long been linked to poor mental function and an increased risk of Alzheimer’s disease. One explanation for this may be that low levels of these B vitamins can lead to high levels of homocysteine (a risk for heart disease), as well as oxidative damage to cells-including brain and nerve cells.
A study conducted at the University of Oxford’s Department of Clinical Neurosciences involved 156 elderly patients who showed mild cognitive impairment and a high risk of dementia and Alzheimer’s disease. The patients were divided into two groups: one took a daily supplement containing 800 mcg of folic acid, 20 mg of vitamin B6, and 500 mcg of vitamin B12; the other group took a placebo.
Researchers used magnetic resonance imaging (MRI) to measure levels of grey matter in patients’ brains; atrophying (shrinking) grey matter is a sign of the progression of Alzheimer’s disease and other forms of dementia. Subjects given B vitamins had about seven times less grey matter shrinkage than did those in the placebo group at the end of the two-year study.
Vitamin K2 Significantly Boosts Bone Health
Vitamin K is required for the production of osteocalcin, a bone protein that anchors calcium molecules and holds them in place within bones. As you might guess, a vitamin K deficiency contributes to weak bones caused by inadequate levels of osteocalcin.
Some research has shown that low bone mineral density (BMD) directly correlates with low levels of circulating vitamin K. Interestingly, more recent studies suggest otherwise: meager vitamin K status does not appear to be associated with less-than-optimal BMD. However, low dietary levels of vitamin K have been linked to fractures. Most likely, vitamin K helps prevent fractures by increasing the tensile strength of bone without affecting BMD.
In a major clinical trial, scientists found that taking MK-7 (a longer-chain form of vitamin K2) produced impressive results on bone health. In the study, 244 healthy postmenopausal women took 180 mcg per day of MK-7 or a placebo for three years. MK-7 was shown to improve vitamin K status and osteocalcin levels. Subjects in the supplement group also experienced a slower decline in age-related BMD levels at the lumbar spine and femoral neck. The MK-7 group’s bone strength was also favorably affected, thereby reducing fracture risk.
MK-7 is found in natto (a fermented soy food). Available in a variety of supplements, MK-7 has been found to be more bioavailable than other forms of vitamin K.
Magnesium Lowers Heart Disease Risk
Researchers at Harvard’s School of Public Health conducted an analysis of 16 studies involving more than 313,000 people that examined the link between low magnesium levels and stroke and heart disease risk.
Scientists found that higher blood levels of magnesium were associated with a 30 percent lower risk of heart disease, and that higher dietary intakes of this important mineral brought about a 22 percent reduced risk of heart disease.
It’s estimated that between seven and eight out of every 10 adults in the United States do not get the recommended daily intake for magnesium.
PS Improves Memory and ADHD
Phosphatidylserine (PS) plays a major role in determining the structure, integrity, and function of the membranes of brain cells. Normally, these cells can manufacture enough PS, but there is evidence that insufficient production is common, especially in people over age 50 and in children with ADHD.
In a landmark study, 36 children aged 4-14 who had not previously received any drug treatment related to ADHD took 200 mg per day of PS or a placebo. After two months, those who received PS showed significant improvements in ADHD symptoms, including better focus and less impulsive behaviors.
Vitamin D Reduces Ear Infections
A growing pile of research shows that at least 50 percent of the general population and 80 percent of infants are likely deficient in vitamin D. And similar research shows that vitamin D supplements may be the most cost- effective strategy for improving health, reducing disease, and living longer. Vitamin D’s role immune cell function, specifically, has gained increased recognition over the past decade, as the vitamin has been shown to produce a wide range of immune health benefits, including:
- Enhancing immune cells’ ability to get rid of viruses and bacteria.
- Balancing immune function by directly impacting T-cell activation.
- Protecting against the development of autoimmune diseases.
- Reducing the frequency of viral-related upper respiratory infections.
New findings show that the sunshine vitamin helps to reduce ear infections. In a randomized study involving 116 children with a history of recurrent ear infections, 1,000 IU daily of vitamin D3 for four months was shown to lower ear infection risk by roughly 50 percent. In the vitamin D group, 26 of the 58 kids developed ear infections compared to 38 of 58 given placebos.
Most experts recommend taking 2,000-5,000 IU of vitamin D3 daily.
Refined Carbs Trigger Food Addiction
Addiction is linked to activity in an area named the nucleus accumbens, sometimes called the brain’s “pleasure center.” This cluster of brain cells modulates the effects of dopamine-the neurotransmitter that seeks to motivate and reinforce behavior, good or bad.
Scientists from Boston Children’s Hospital and Harvard Medical School found that consuming a meal high in refined carbohydrates stimulates the nucleus accumbens, acting in much the same way as cocaine and heroin. The researchers also observed in subjects increased hunger, decreased glucose, and regions of the brain stimulated for hours after eating-a critical period that affects eating behaviors at the next meal.
This is the first study of its kind to demonstrate that refined carbohydrates cause symptoms consistent with addiction. The scary truth? Foods that quickly raise blood sugar levels, especially concentrated sources of refined sugars, alter brain activity to make us crave them even more.
At least 50% of the general population and 80% of infants are likely deficient in vitamin D.
Michael T. Murray, ND, is the author of more than 30 books on natural health, including The Encyclopedia of Natural Medicine, Third Edition. He is regarded as one of the world’s top authorities on natural medicine, and is a sought-after lecturer and educator. Visit him online at doctormurray.com.