Scientists have found evidence supporting the health benefiting facts about certain foods like green tea and apples.

Dr Paul Kroon and his team at the Institute of Food Research have shown that polyphenols in green tea and apples block a signalling molecule called VEGF, which in the body can trigger atherosclerosis and is a target for some anti-cancer drugs.

In the body, VEGF is a main driver of blood vessel formation in these cell types via a process called angiogenesis. Angiogenesis is crucial in cancer progression, as well as in the development of atherosclerotic plaques and plaque rupture which can cause heart attacks and stroke.

Using cells derived from human blood vessels, the researchers found that low concentrations of the polyphenols epigallocatechin gallate (EGCG) from green tea and procyanidin from apples stopped a crucial signalling function of VEGF.

Inhibition of VEGF signalling by dietary polyphenols has previously been implicated in other studies, but this study provides the first evidence that polyphenols can directly interact with VEGF to block its signals, at the levels you would see in the blood stream after eating polyphenol rich foods.

Kroon said that if this effect happened in the body as well, it would provide very strong evidence for a mechanism that links dietary polyphenols and beneficial health effects.

The fatty acids that fish oil contains are vitally important to the developing brain, says a new study, suggesting that women maintain a balanced diet rich in these fatty acids for themselves during pregnancy and for their babies after birth.

Dietary deficiencies in the type of fatty acids found in fish and other foods can limit brain growth during foetal development and early in life, the findings showed.

Deficits in what are known as n-3 polyunsaturated fatty acids cause molecular changes in the developing brain that result in constrained growth of brain cells and the synapses that connect them, said Susana Cohen-Cory, professor of neurobiology and behaviour at the University of California, Irvine (UCI).

These fatty acids are precursors of docosahexaenoic acid, or DHA, which plays a key role in the healthy creation of the central nervous system.

Dietary DHA is mainly found in animal products: fish, eggs and meat. Oily fish - mackerel, herring, salmon, trout and sardines - are the richest dietary source, containing 10 to 100 times more DHA than non-marine foods such as nuts, seeds, whole grains and dark green, leafy vegetables.

In their study, which used female frogs and tadpoles, the UCI researchers were able to see how DHA-deficient brain tissue fostered poorly developed neurons and limited numbers of synapses, the vital conduits that allow neurons to communicate with each other.

"Additionally, when we changed the diets of DHA-deficient mothers to include a proper level of this dietary fatty acid, neuronal and synaptic growth flourished and returned to normal in the following generation of tadpoles," Cohen-Cory said.

The study appeared in The Journal of Neuroscience.

Birth control pills may shrink portions of a woman's brain and affect its function, scientists have warned.

It's possible that the synthetic hormones found in the pill - and possibly the suppression of natural hormones that occurs when women are using the pill - cause these alterations in brain structure and function, according to a new study.

Researchers at the University of California, Los Angeles in a study conducted on 90 women found that two key brain regions, the lateral orbitofrontal cortex and the posterior cigulate cortex, were thinner in women who used oral contraception than in those who did not.

The lateral orbitofrontal cortex plays an important role in emotion regulation and responding to rewards, while the posterior cigulate cortex is involved with inward-directed thought, and shows increased activity when we recall personal memories and plan for the future.

Changes in the lateral orbitofrontal cortex could be responsible for the increased anxiety and depressive symptoms that some women experience when they start taking the pill, researchers said.

"Some women experience negative emotional side effects from taking oral contraceptive pills, although the scientific findings investigating that have been mixed," Nicole Petersen, a neuroscientist at UCLA and the study's lead author, told 'The Huffington Post'.

"So it's possible that this change in the lateral orbitofrontal cortex may be related to the emotional changes that some women experience when using birth control pills," Petersen said.

Researchers are yet to determine if these neurological changes are permanent, or if they only last while a woman is on the pill.

The study was published in the journal Human Brain Mapping.

Production of a key chemical, deficiency of which is linked to various diseases and disorders such as depression and anxiety, depends largely on a group of approximately 20 bacteria in the gut, says a new study.

Certain bacteria in the gut are important for the production of serotonin, which is well known as a brain neurotransmitter, the findings showed.

In fact, altered levels of this peripheral serotonin have also been linked to diseases such as irritable bowel syndrome, cardiovascular disease, and osteoporosis.

"Our work demonstrates that microbes normally present in the gut stimulate host intestinal cells to produce serotonin," said first author of the study Jessica Yano from the California Institute of Technology.

Peripheral serotonin is produced in the digestive tract by enterochromaffin (EC) cells and also by particular types of immune cells and neurons.

While previous work in the field indicated that some bacteria can make serotonin all by themselves, this new study suggests that much of the body's serotonin relies on particular bacteria that interact with the host to produce serotonin, Yano noted.

The researchers wanted to find out whether specific species of bacteria, out of the diverse pool of microbes that inhabit the gut, are interacting with EC cells to make serotonin.

They identified several particular metabolites -- products of the microbes' metabolism -- that were regulated by spore-forming bacteria and that elevated serotonin from EC cells in culture.

Furthermore, increasing these metabolites in germ-free mice increased their serotonin levels.

"Serotonin is an important neurotransmitter and hormone that is involved in a variety of biological processes. The finding that gut microbes modulate serotonin levels raises the interesting prospect of using them to drive changes in biology," senior author of the study Elaine Hsiao from the California Institute of Technology pointed out.

The study appeared in the journal Cell.

Scientists have bred a new version of broccoli, consuming which can help cut down blood LDL-cholesterol levels by around 6 percent.

The broccoli variety was bred to contain two to three times more of a naturally occurring compound glucoraphanin. It is now available in supermarkets, under the name Beneforte.

Working with colleagues at the University of Reading, in two independent studies, the researchers gave a total of 130 volunteers 400g of the high glucoraphanin broccoli per week to include in their normal diet. Human trials were led by the Institute of Food Research.

After 12 weeks, they saw the levels of LDL-cholesterol in their blood drop by an average of about 6 percent. Elevated LDL cholesterol is a recognized risk factor for heart disease.

Although the reduction seen in these trials is small, at a population level, a 1 percent reduction in LDL-cholesterol has been associated with a 1-2 percent reduction in risk of coronary artery disease.

High glucoraphanin Beneforte broccoli was developed using traditional breeding techniques at IFR's partners on the Norwich Research Park, the John Innes Centre and the University of East Anglia, and Seminis Vegetable Seeds Inc.

Other foods or ingredients that have been proven to lower LDL-cholesterol are beta-glucans in oats and plant stanols. These work by reducing cholesterol absorption into the body. As glucoraphanin works by reducing how much our bodies make, eating these foods together is likely to have an additive effect.

The study is published in the journal Molecular Nutrition and Food Research.