Plant-based diets can be potent in preventing prostate cancer
Genetic factors can play an important role in prostate cancer but lifestyle and diet choices are crucial – they can significantly increase or reduce the risk. Obesity poses a particular risk because it raises the levels of sex hormones which, in turn, increase the risk of this hormone-sensitive cancer. Some sexually transmitted diseases have been linked to a higher risk too, as well as physical inactivity, smoking and alcohol consumption.
As more and more plant milks are popping up, you may be wondering about their health benefits and how they compare to cow's milk. Veronika Powell explores the milky landscape
Firstly, let's have a proper look at what any milk actually is - a very watery liquid, around 90 per cent is always water. Therefore, any amount of nutrients it contains is more or less diluted and any health effects depend on how much of it you drink.
New study shows how a healthy vegan diet can cut your risk of type 2 diabetes in half
This was the first study to distinguish not just between animal and plant-based diets but also between healthy and unhealthy plant-based diets. Healthy foods included wholegrains, fruits, vegetables, nuts, pulses, vegetable oils, tea and coffee; whilst unhealthy foods included animal products, fruit juices, sweetened beverages, refined grains (white bread, cornflakes etc.), potatoes, sweets and desserts.
A large analysis of hundreds of studies set out to look at the health effects of many food groups and has confirmed that plant foods are more protective than animal foods against chronic diseases that are related to diet.
According to the study, fruit and vegetables are extremely protective, showing the ability to significantly reduce the risk of heart disease, cancer and obesity. The only negative effect – a higher risk of digestive cancers – possibly stems from increased consumption of pickled vegetables.
An extensive analysis of studies that looked at pulse consumption (beans, lentils, soya, chickpeas, peas) and the risk of colorectal cancer showed interesting results. People who eat more pulses have a lower risk of this type of cancer. In particular, both the intake of fibre from pulses and the intake of soya were associated with a lower colorectal cancer risk.
Early onset of menarche (the first period) may negatively influence the future health of women – in particular, it has been linked to an increased risk of hormone-related cancers such as ovarian and breast. Some types of food have been implicated (meat, milk, animal protein and fats in general) and to clarify whether soya can play a role, a team of scientists examined this in a high soya-consuming population.
The results of a long-term (over 13 years) study of nearly 50,000 women of all ethnicities revealed that regular intake of plant substances called isoflavones can significantly reduce the risk of endometrial cancer. Endometrial cancer usually means cancer of the inner lining of the uterus but it can spread or affect surrounding tissues. Isoflavones are plant substances (most commonly found in soya foods but also in other pulses such as beans and lentils), which can act as very mild oestrogens in the body.
To establish whether soya is definitely safe for women with breast cancer, almost 10,000 women were followed for several years and their diets analysed. To examine the possibility of cultural and lifestyle influences, the study included North American and Chinese women. The results of this largest study to date on soya and breast cancer showed that for all women alike, soya consumption after the breast cancer diagnosis slightly decreased the risk of death and significantly decreased the risk of developing a new tumour.
A refreshingly original long-term study of several hundred elderly women found that a daily intake of pulses and soya products was associated with a significantly reduced risk of functional disability in later life. People with functional disabilities have problems, for example, with going outside the home, keeping track of money and bills, preparing meals, doing light housework, taking prescription medicines in the right amount at the right time, and using the telephone.
There have been a number of studies investigating the effects of soya isolates (eg extracted soya protein) on human health but not so many using soya foods as they are normally eaten. A recent study did just that as it was aimed at investigating the effect of soya milk consumption on cholesterol levels in blood. High cholesterol is responsible for furred up arteries so it’s important to keep your cholesterol in check in order to stay healthy. Healthy young to middle-aged volunteers consumed soya milk daily for a period of 21 days.
Soya foods may confer many health benefits, including protection against heart disease, diabetes, menopausal symptoms, osteoporosis, breast cancer and prostate cancer, they may even improve cognitive function.
The National Toxicology Program (NTP) – an American institution – released its draft opinion on the potential of soya infant formula to cause adverse human developmental effects. Soya formula was labelled as being of “minimal” concern level and one of the experts stated that soya formulas have been used for over 50 years without reports of negative reproductive or developmental effects.
An article in the journal Nutrients reviewed more than 200 scientific papers on soya published in recent years with regard to specific soya bean constituents, especially isoflavones. The article highlighted the role that soya foods have in reducing risk of heart disease, osteoporosis and certain forms of cancer and concluded that concerns about adverse effects of soya consumption were not scientifically supported.
Previous studies show that soya protects against breast cancer. This study looked at the diets of 34,028 women in the Singapore Chinese Health Study among whom there were 629 breast cancer cases. Results showed that postmenopausal women who consumed the most soya, fruits and vegetables had a 30 per cent lower risk of developing breast cancer compared with those who consumed the least. The longer they had consumed these foods, the lower their risk of developing breast cancer.
There is strong evidence that eating soya food in adolescence can protect against breast cancer later in life. New evidence suggests that soya may also offer protection to women who have had this disease. The Shanghai Breast Cancer Survival Study looked at over 5,000 women diagnosed with breast cancer an average of four years previously.
New research from the Journal of Nutrition shows that soya foods can lower cholesterol levels in people with type 2 diabetes. They found that 40 grams of soya protein per day for 57 days significantly reduced cholesterol, compared to milk protein. Lead researcher Dr Alison Duncan said: “This study provides evidence for soya as a dietary preventive strategy for adults with type 2 diabetes to reduce their cardiovascular disease risk and, in so doing, improve their quality, and possibly length, of life.”
A new study from the American Journal of Clinical Nutrition reports how soya foods can lower the risk of prostate cancer by up to 26 per cent. Interestingly the research found that while non-fermented soy foods (tofu and soya milk) lowered the risk, fermented ones (miso and soya sauce) did not.