The 2015 collection of "In-vogue" foods... are they really so fabulous for our health?

By Charlotte Foster BSc (Hons), MSc, RD.

 

 

With the Easter period over and the realisation that summer is on its way,  it’s that time of year again when we brace ourselves for the onslaught of social media posts and comments relating to the “let’s get bikini ready” movement. This includes numerous hashtags left right and centre relating to “#detox” “#clean eating” “#paleo” and countless selfies of gym joiners and photos of mealtimes!

 

2015 was another fabulous year for certain foods who made their catwalk debuts into many peoples’ diets following media claims about their apparent health benefits.

 

We decided to look at some of these fashionable foods and examine the evidence as to whether these really are worth the “designer label” of beneficial for our health.

 

Quinoa

 

Available in three coloured varieties (red, white and black) this versatile, gluten-free seed has muscled its way into our diets, becoming a food phenomenon in recent years.

 

Quinoa is often promoted as being a food staple for anyone trying to lose weight/ shape up. It is often found lurking in many recipe books as the carbohydrate base to dishes and yet, compare to other carbohydrate sources, is the highest protein containing “grain” (containing all the essential amino acids we need) and a good source of fibre (1).

 

Quinoa is a dietary source of magnesium, zinc, potassium, and iron. However, it also contains phytic acid which can inhibit the absorption of these minerals and oxalates which can inhibit calcium absorption (1). Soaking quinoa before cooking it can help reduce the phytic acid content.

 

Quinoa also contains some plant based antioxidants and flavonoids. Research has showed that flavonoids called “quercetin” and “kaempferol” have been shown to have anti-cancer (2)  and anti-inflammatory (3). However, these findings were found in animal studies and so further research is needed to ascertain whether this would be the same for humans!

 

Once upon a time, sourcing quinoa in the UK was quite a challenge. Quinoa tended to be available at a high cost exclusive to whole food and independent shops. However, nowadays you can pick up a bag in your local supermarket relatively easily and cheaply making it an accessible cupboard food item for all budgets.  However, this has come at a cost for the local populations where quinoa comes from. Native to populations in the Bolivian Andes quinoa used to be a staple crop, but nowadays due to demand from western markets causing high prices, many locals with low incomes can no longer afford this nutritious grain (4).

 

Conclusion: Due to its versatility, nutritional value and ability to accommodate a range of special dietary requirements, quinoa seems to offer many appealing qualities. However, for ethic-conscious eaters the cost-benefit to the local populations and impact on carbon foot print may not justify the buy!  

 

 

Kale

 

This designer leaf comes in number of varieties. They come dressed in green or purple with curly or smooth leaves and are members of the cabbage family.

 

This nutritious cruciferous vegetable is packed with antioxidant vitamins, particularly vitamin A (beta-carotene) and vitamin C (needed for the body’s structural protein “collagen” production). These antioxidants help minimise oxidative damage which is linked to cancer development.  Similarly to quinoa, kale contains the flavonoids “quercetin” and “kaempferol” associated with anti-cancer and anti-inflammatory properties in animal studies (see above) (2, 3). It is a good plant source of calcium and contains sources of potassium and magnesium.

 

Conclusion: As one of your 5 a day this leafy number has many antioxidant vitamins and minerals to enhance your diet. However, we need to remember it’s variety and an array of different fruits and vegetables which will give us the spectrum of the nutrients we need for a healthy and balanced diet.

 

 

Matcha Powder

 

 

This popular food supplement powder comes from the same plant as green tea or “Camellia sinensis”.  However, matcha powder undergoes several different processing stages compared with green tea. This processing boosts the amino acid content of the leaves compared with standard green tea. Unique to both green tea and matcha powder (in a higher concentration) is the amino acid “L-theanine” (5).

 

Matcha powder is made using the whole leaf being crushed into a powder whereas in green tea water is infused with the leaves to leach out the nutritients.   Therefore, it is recommended that no more than 2 cups of matcha tea are consumed/day due to the high concentration of nutrients and contaminants (e.g. heavy metals and pesticides which are associated with all types of tea) (6). Too much matcha tea has been linked with causing nausea and liver toxicity (7,8).

 

 

What are the health claims associated with matcha powder?

 

 

  • Antioxidants – containing ~ 3x more antioxidants compared with green tea (9).

 

  • Possible improvements on blood lipid and glucose levels (although only demonstrated in mice studies) (10).

 

 

What are the health claims associated with green tea?

 

  • Weight loss – green tea is thought to help increase metabolic rate, it is a popular ingredient in weight loss pills. However, a study in 2012 found there were no statistically significant findings to support this (11)

 

  • Possible improvements on cholesterol levels (NB studies were done in American populations) (12, 13).

 

  • Relaxation – the unique amino acid “L-theanine” in green tea and matcha powder has been linked to inducing mental relaxation without initiating drowsiness (5).

 

 

Conclusion: It would seem that compared with green tea, the benefits are minimal. Yes, gram for gram matcha powder is 3+ times more antioxidant rich, but too much of a good thing can be detrimental. Green tea is cheaper on the wallet too! Either way, let’s not kid ourselves that by drinking matcha or green tea we are going to miraculously lose weight (unless that was all that we drank!) and at the risk of getting liver/kidney damage, we don’t think it’s worth the risk!

 

 

Nut butters

 

We all recognise peanut butter as a sandwich filler staple, but nowadays you can find food retailers selling all kinds of nut and seed butter alternatives such as:

 

  • Peanut butter & peanuts = one of the highest protein contents (14)

 

  • Almond butter & almonds =high in vitamin E (14)

 

  • Cashew butter & cashews = rich in magnesium (14)

 

  • Pistachio butter &  pistachios = high in lutein (antioxidant found in green leafy veg) (14)

 

  • Walnut butter & walnuts = high in omega-3 and antioxidants (14)

 

 

Pros and Cons of nut butters:

 

Pros:

 

 

  • Usually rich in mono unsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) which can help lower low density lipoprotein (LDL) cholesterol levels (14,15).

 

  • Good source of protein, vitamins and minerals (14).

 

  • Energy and protein dense – useful for fortifying foods for those trying to gain weight.

 

  • The variety of nut butters available can be useful for people with peanut (only) allergy.

 

  • Smooth varieties (no chunks of nuts) can be enjoyed by people who have difficulty chewing or who may have been advised to follow textured modified diets.

 

 

Cons:

 

 

  • Often energy dense (high in calories) – watching portion sizes is important for those trying to lose weight.

 

  • Due to processing, the fibre contents are lower in comparison to whole nuts.

 

  • Varieties can have hidden salt/sugar/ fat added (check the labels).

 

 

Conclusion: Nuts and seeds are very nutritious for the reasons outlined above. Nut butters can be enjoyed as part of a healthy and balanced diet and may be a useful depending on your dietary aim.  If you are simply wishing to follow a balanced diet and maintain a healthy weight, one could argue that having a handful of unsalted whole nuts would be beneficial giving you the nutrients with a higher fibre content which helps to reduce the amount of fat absorbed compared with blended nut butters. As well as this, whole nuts can often be bought at a cheaper price without the additions of extra salt/sugar and oil.

 

 

Coconut oil

 

2015 saw this exotic number strut not only into our diets but also our beauty regimes!

 

Coconut oil is produced from the white flesh of the nut which is compressed to extract tropical tasting oil. It is solid at room temperature (similar to butter/lard) due to the high in saturated fat content.  >90% of the energy (calorie) content comes from saturated fat compared with 14% in olive oil (16). However, unique to coconut oil its saturated fat composition comes from medium chained triglycerides (MCTs) – which are metabolised differently. MCTs are converted into ketone bodies which have demonstrated to have effects on the brain (16).  – with research ongoing into the effects on Alzheimer’s and epilepsy. However, further more robust research is required in order to confirm health claims.

 

Coconut oil also contains lauric acid which is broken down in the gut to “2-mono-laurin”  which helps to dissolve the lipid membrane of certain pathogens (17).

 

Another claim that has us hooked is that coconut oil can supposedly help lower our total cholesterol by raising the high density lipoproteins (HDL), good cholesterol. However, saturated fat can increase the low density lipoproteins (LDL), bad cholesterol associated with heart disease (18).  Sticking with the “old-school” advice of choosing unsaturated fat alternatives e.g. olive/sunflower/vegetable oil has also demonstrated to have an effective way to help reduce LDL cholesterol levels (18), so surely these would be healthier and more cost-effective options?

 

Conclusion: Whilst there may be several possible benefits of coconut oil, it is nonetheless still a type of fat! Like all sources of fat in the diet they are energy (calorie) dense. Whilst it’s fine to use in moderation within the diet, the hype around this product can often encourage people to use the oil in excess. Diets high in saturated fat are associated with increased risk of cardiovascular disease. We aren’t quite convinced that the health claims are built on robust evidence and like all fats we would advise these are limited (unless advised otherwise by a dietitian/ medical professional).  

 

 

Coconut water

 

Bananas are soooo last season! Move over and make way for this potassium fuelled beverage!

 

Coconut water comes from the young green coconuts – different to coconut milk produced from the white flesh of the matured nut.

 

Once marketed as “super hydrating” and “nutrient packed” due to its electrolyte content, coconut water may not be all that its cracked up to be.  Ironically, a study funded by a brand of coconut water “Vita Coco” demonstrated that there was little difference in the performance or hydration of men who drank bottled water, coconut water or a sports drink (19).   

 

With no evidence to support such health claims a lawsuit was filed against the company to revise the falsely advertised health claims.  Click here for a further information about the lawsuit. 

 

 

Conclusion: It appears that we’ve gone coco-nuts in believing the claims and marketing behind this juice. If you’re looking for dietary sources of potassium then this might be something to consider, but it’ll cost you! Bananas contain excellent sources of potassium and fibre for under 20p a pop! However, if you’re bored of water one could argue that compared with most sports drinks which are often loaded with excessive sugar, this may be a more nutritious option.  

 

 

Chia seeds

 

 

Tiny in stature, these South American mini seeds are mighty and nutritious in number! A distant relative of the mint plant, chia seeds are famous for being a good plant based source of omega-3 fatty acids known as alpha linolenic acid (ALA) which are essential to our diet as they cannot be produced by the body (20).

 

The nutrition CV doesn’t stop there! These seeds are rich sources of soluble fibre, protein, vitamins (A&B) and minerals (calcium, magnesium, manganese and phosphorous.

 

With a mild flavour, these can be added to smoothies, sprinkled on cereals, salads and nowadays are popular in forming puddings and deserts due to the fact that they swell to form a gelatinous texture when in contact with liquid. When soaked in water they can also be used as an egg replacement, giving a perfect solution for those with egg allergies! Simply mix 1tbsp chia seeds with 3 tbsp water (per egg equivalent).

 

Conclusion: Arguably, linseeds (flax) seeds are another fabulous source of omega-3 and are often more cheaper than chia seeds. However, the overall nutritional profile of chia seeds appears to be slightly superior.

 

 

References

 

(1):Food and Agricultural Organisation (FAO’s) International Year of Quinoa 2013 website (http://www.fao.org/quinoa-2013/what-is-quinoa/nutritional-value/en/ )

 

(2): Murakami, A., Ashida, H. and Terao, J. (2008) Multitargeted cancer prevention by quercetin. Cancer Letters 269 (2) 315-325.

 

(3): Stewart, L.K., Soileau, J.L., Ribnicky, D., Wang, Z.Q., Raskin, I., Poulev, A., Majewski, M., Cefalu, W.T. and Gettys, T.W. (2008) Quercetin transiently increases energy expenditure but persistently decreases circulating markers of inflammation in C57BL/6J mice fed a high-fat diet. Metabolism 57 (7); S39-46.

 

(4): ResponsAibility Investments (2015) Quinoa: Exploring the market dynamics of an Andean staple- Case study. Available at http://www.responsability.com/funding/data/docs/en/15566/rA-Case-Study-Quinoa-EN-final.pdf [last accessed 21/03/16].

 

(5): Nobre, A.C., Rao, A. and Owen, G.N. (2008) L-theanine, a natural constituent in tea, and its effect on mental state. Asia Pacific Journal of Clinical Nutrition 17 (1); 167-168.

 

(6):  Schwalfenberg, G. Genuis, S.J. and Rodushkin, I. (2013) The benefits and risks of consuming brewed tea: beware of toxic element contamination. Journal of Toxicology 2013:370460.

 

(7): Galati, G., Lin, A., Sultan, A.M., O’Brien, P.J. (2006) Cellular and in vivo hepatotoxicity caused by green tea phenolic acids and catechins.  Free Radical Biology & Medicine 40(4); 570-580.

 

(8): Mazzanti, G., Menniti-Ippolito, F., Moro, P.A., Cassetti, F., Raschetti, R., Santuccio, C. and Mmastrangelo, S. (2009) Hepatotoxicity from green tea: a review of the literature and two unpublished cases. European Journal of Clinical Pharmacology 65 (4); 331-341.

 

(9): Weiss, D.J. & Anderton, C.R. (2003) Determination of catechins in matcha green tea by micellar electrokinetic chromatography. Journal of Chromatography 1011 (1-2); 173-180.

 

(10): Xu, P., Ying, L., Hong, G. and Wang, Y. (2016) The effects of the aqueous extract and residue of Matcha on the antioxidant status and lipid and glucose levels in mice fed a high-fat diet. Food & Function 7 (1); 294-300.

 

(11): 5: Jurgens, T.M., Whelan, A.M., Killian, L., Doucette, S., Kirk, S. and Foy, E. (2012) Green tea for weight loss and weight maintenance in overweight or obese adults. Cochrane Database Systematic Review 12.

 

(12): Kim, A., Chiu, A., Barone, M.K., Aving, D., Wang, F., Coleman, C.I. and Phung, O.J. (2011) Green tea catechins decrease total and low-density lipoprotein cholesterol: a systematic review and meta-analysis. Journal of American Dietetic Association 111(11); 1720-1729.

 

(13):  Zheng, X.X., Xu, Y.L., Li, S.H., Hui, R. and Huang., X.H. (2011) Green tea intake lowers fasting serum total and LDL cholesterol in adults: a meta-analysis of 14 randomized controlled trials.American Journal of Nutrition 94(2); 601-610.

 

(14): Ros, E. (2010) Health Benefits of Nut Consumption. Nutrients 2(7); 652-682.

 

(15): Kelly, H. and Sabate, J. (2006) Nuts and coronary heart disease: an epidemiological perspective. British Journal of Nutrition  96(2); S61-67.

 

(16): Bhatnagar, A.S., Prasanth Kumar, P.K., Hemavathy., J. and Gopala Krishna, A.G (2009). Fatty Acid Composition, Oxidative Stability, and Radical Scavenging Activity of Vegetable Oil Blends with Coconut Oil. Journal of The American Oil Chemist’s Society 86; 991–999.

 

(17): Enig, M.G. (1998) Lauric oils as antimicrobial agents: theory of effect, scientific rationale, and dietary applications as adjunct nutritional support for HIV-infected individuals. In: Watson RR (ed) Nutrients and foods in AIDS. CRC Press, Boca Raton; 81–97.

 

(18): British Heart Foundation (2016) I’ve heard coconut oil is good for you. Is this true? Available at https://www.bhf.org.uk/heart-matters-magazine/nutrition/ask-the-expert/coconut-oil [last accessed 21/03/16].

 

(19):  Kalman, D.S., Feldman, S., Kreiger, D. and Bloomer, R.J. (2012) Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men. Journal of International Sports Nutrition 9;1.

 

(20): Academy of Nutrition and Dietetics (2013). Aztec Diet Secret: What Are Chia Seeds? Available at http://www.eatright.org/Public/content.aspx?id=6442472548 [last accessed 21/03/16].