SPECIAL REPORT: Food Trends and “Fad” Diets

27 Jun 2016 --- Like fashion, diet crazes come and go. NutritionInsight looks at some of the latest food trends to see which diets can aid in safe weight loss and improving health, and which are just “fads.” A “fad” diet promises quick weight loss through what is usually an unbalanced diet. Below are five popular food regimes: but are they simply in vogue for the moment, or will their popularity continue?

Flexitarian diet
The flexitarian diet is a primarily vegetarian but also includes occasional meat or fish. This inclusive form of semi-vegetarianism has seen an increase in popularity, as more and more people are reducing meat products in their diets thanks in part to international campaigns such as Meat Free Monday to improve health as well as sustainability of the planet.

Research also seems to favour the health benefits linked to this plant-based diet. A 2015 study found that a semi-vegetarian diet effectively lowers the risk of cardiovascular disease (CVD) and stroke. Researchers followed over 450,000 Europeans for around 10 years and found that those who ate the most “pro-vegetarian” diets (at least 70% of food coming from plant sources) had a 20% lower risk of dying from CVD than those who ate more meat.

But does this diet aid in weight loss? Yes, as flexitarians have been found to weigh 15 pounds less. They also have lower rates of diabetes and cancer, as well as live up to 3.6 years longer. 

Essentially, flexitarianism is not just about eating less animal products, but more about making smarter food choices in general. 

Paleo diet
This diet (also known as the Paleolithic Diet, the Caveman diet and the Stone Age Diet) is based on the low-fat foods presumed to have been eaten by early humans, consisting chiefly of meat, fish, vegetables, and fruit. Coffee, alcohol and processed foods, as well as dairy and cereal products, are excluded.

This diet has been linked to decreasing risk of diabetes and CVD in postmenopausal obese women. However, it has also been linked to increasing weight gain, and the British Dietetic Association has deemed this diet a “Jurassic fad!”: 

“A diet with fewer processed foods, less sugar and salt is actually a good idea, but unless for medical reason, there is absolutely no need to cut any food group out of your diet. In fact, by cutting out dairy completely from the diet, without very careful substitution, you could be in danger of compromising your bone health because of a lack of calcium. An unbalanced, time consuming, socially isolating diet, which this could easily be, is a sure-fire way to develop nutrient deficiencies, which can compromise health and your relationship with food,” the BDA state.

Sirtfoods diet
This year the world was introduced to the Sirtfoods Diet plan which is “a celebration of food that makes you want to pick up a knife and fork, not lay them down,” according to its devisors Aiden Goggins and Glen Matten.

Unlike other diets, red wine, dark chocolate, coffee, and kale are welcome in the 2-stage, 3-week diet plan, as they are said to activate sirtuin (SIRT) proteins and switch on the so-called “skinny gene” pathways in the body. Celebrities have claimed to lose 7 pounds in 7 days after using the diet, and fans praise the increase in muscle mass, wellness and energy that also result. Other benefits of this diet include lowering risk of diabetes, CVD, and Alzheimer’s disease.

5:2 diet
The 5:2, or fast diet, is a diet which stipulates calorie restriction for two days a week – recommendations are usually around 500 calories for women and 600 for men – and unconstrained eating the other five days. 

But how does this diet make users lose weight? Researchers from the University of Florida suggest that the drop in blood sugar that results from intermittent fasting (IF) pushes cells to work harder to utilize other forms of energy as a small increase in free radical production early on during fasting.

They state: “We found that in response to fasting every other day, the cells made more copies of a gene called SIRT3, which is part of a pathway that works to prevent free radical production and improve cellular repair processes.”

“We also found a significant decrease in levels of circulating insulin, a sign that the participants’ bodies were more responsive to this hormone. This is important because when we become less sensitive to insulin, we are at risk for diabetes.”

However, they conclude: “One somewhat surprising finding is that when participants took daily oral supplements of Vitamin C and E, the benefits from fasting disappeared.” 

Fasting is something that human beings have practiced throughout history, often out of circumstance rather than choice. These findings suggest that fasting is actually good for our bodies, and that antioxidant supplements, while potentially good at certain times, might actually prevent normal healthy cellular responses in other situations.

Now, new British research from the Genesis Breast Cancer Prevention Centre in South Manchester has linked the 5:2 diet to preventing breast cancer.

The 24 overweight or obese women in the study, aged 35 to 45, were free of cancer or diabetes, and had a higher than average breast cancer risk. They were told to reduce their calorie intake by 75% on two consecutive days a week, and follow a Mediterranean diet for the remaining five. 

The women lost weight and body fat – about 5% for both – and registered positive changes in the way their bodies were handling energy, fat and insulin. Around half the women showed biochemical changes in their breast tissue that was interpreted as potentially related to breast cancer risk. However, the changes found in such a small group cannot prove that a 5:2 diet would reduce breast cancer risk in all women. 

Gluten-free diet
Recent studies by Weetabix showed that almost a third – or 32% – of British people avoid wheat because of celebrity “fad” diets. In the UK, the majority of people eat just 18g of fiber a day instead of the recommended 30g. 

Gluten is a mixture of proteins found in wheat and related grains, including barley, rye, oat, and all their species and hybrids (such as spelt, kamut, and triticale). 

Celiac disease is a serious illness where the body’s immune system attacks itself when gluten is eaten. It occurs in about 1% of the population, and sufferers of the disease need to cut every trace of gluten out of their diet. 

The gluten-free food industry is now a multi-billion-dollar industry. However, diets omitting gluten can contain added sugars and fat, which can result in weight gain. Items such as beer, bread, pasta, sushi, as well as candies, dietary supplements, sauces and seasonings can contain gluten, making this diet quite hard to stick to.

According to Coeliac UK, which is the oldest and largest celiac disease charity in the world, some people have non-celiac gluten sensitivity: gut symptoms when eating foods with gluten-containing ingredients, even if they don’t have celiac disease. Nevertheless, more people are removing gluten from their diets, believing if barley, rye and wheat are harmful to people with celiac disease, they must also be harmful to everyone.

Some nutritionists and chemists recommend gluten-free diets to reduce inflammation, prevent auto-immune diseases, treat fatigue and depression, and also for autism. However, this does not seem to be based on scientific evidence. 

As recently as last week, experts warned against gluten free diets. In the largest study of its kind so far, researchers from Harvard University revealed that wheat, which is rich in many components – including dietary fiber, starch, fat, antioxidant nutrients, vitamins, minerals, lignans and phenolic compounds – can reduce the risk of certain cancers and CVD. Studies have also shown that whole grain cereals can help to protect against obesity and diabetes. 

“Fad” diets are targeted at people who want to lose weight quickly without exercise. As there are positives and negatives seen in these diets, it looks like these eating regimes will continue to make the headlines for some time to come.

by Kerina Tull