Spinach and feta hummus and does the scientific literature support the claims about conjugated linoleic acid and fat loss?

Spinach and feta hummusThis dip is good. I bought a tub of Spinach and feta hummus at a farmers market in Venice Beach when I was in L.A. in October last year. I pulled off the label to remind myself to make a version of this dip when I returned home. I happened to find that label over the weekend while I was cleaning up.

Not only is this dip tasty but it is nutritious too. Spinach provides minerals such as iron and calcium, the chickpeas provide dietary fibre and the feta cheese is a source of protein. Also, I had a look in the scientific literature and discovered that feta cheese is a major dietary source of conjugated linoleic acid (CLA) (1). I had not heard of this fatty acid before so I did some research. CLA is a natural, but minor, component of fats from ruminant animals that enters the human diet via meat and dairy products (2). CLA has been reported to have a range of biological effects, including anti-carcinogenesis (anti-cancer), anti-atherogenesis, altering immune function and the most controversial and studied effect of CLA, the potential influence on body composition (3). CLA has become a popular weight lose supplement especially after it was approved by the Food and Drug Administration for Generally Recognized as Safe status in the U. S. in 2008 .

Conjugated linoleic acid and fat loss

Due to the current epidemic of obesity and associated diseases, there has been A LOT of studies out there investigating the effects of CLA on weight loss. Most of the studies conducted on animals have found that CLA reduces body fat when compared to controls. Mice are the most responsive with reports of CLA treated animals having up to 88% more fat loss compared to controls (4 – 6). Results of animal studies have also revealed that only a particular isomer of CLA, the trans-10, cis-12 (t10, c12 or 10E,12Z) isomer, can cause fat loss (7, 8).

Of course as a scientist I wanted to know the mechanism behind the reported fat loss induced by CLA. When it comes to fat loss, it seems that the t10, c12 isomer of CLA decreases the amount of fat stored in adipocytes (fat cells). t10, c12 CLA does not kill adipocytes but rather it alters the function of the adipocytes by increasing lipid catabolism (the break down of fats), increasing fatty acid oxidation and reducing glucose uptake and consumption. An inflammatory response and reactive oxygen species are also induced in adipocytes in response to t10, c12 CLA. It seems that exposure to t10, c12 CLA turns white adipocytes into cells that burn fatty acids instead of cells that store lipids, however, this comes with negative consequences (9 – 11). I found this concerning and studies in vitro (in cell lines) and in vivo (in whole organisms eg. animals) have shown that t10, c12 CLA can also have detrimental effects on surrounding cells. These effects include inducing inflammation, hepatic steatosis (fatty liver) and an atherogenic lipid profile (12 – 17).

Human studies involving CLA

A meta analysis conducted in 2007 published in the American Journal of Clinical Nutrition evaluating 18 randomized, double-blind, placebo-controlled human clinical trials of CLA in normal weight, overweight and obese individuals of any age came to the conclusion that CLA has a modest beneficial effect on human body composition (18). However, the majority of these studies were less than 12 weeks in length and while there were no severe adverse events reported in these studies, I would be wary about the long-term effects of CLA use given the evidence above about the mechanism of action on fat cells and the impact it can have on surrounding tissues. I would rather go for a run than try CLA as a fat loss supplement.

Enough science. Here is the recipe.Hummus baked chicken

 Spinach and feta hummus

Ingredients

125 grams frozen spinach

1 400 gram tin of chickpeas, drained and rinsed

100 grams feta cheese

1 clove garlic

1 tablespoon tahini

½ teaspoon cumin

Salt

Method

Thaw the frozen spinach in the microwave with a small amount of water for 3 minutes.

Place all the ingredients, including the frozen spinach, into a food processor and process until all ingredients are combined and a smooth paste is formed.

Total cost = $3.30 based on ingredients purchase from Aldi excluding the tahini.

This hummus is great as a dip with carrot sticks, as a dressing on a salad or baked on chicken breast. To make Hummus baked chicken, place a chicken breast on a baking tray lined with baking paper. Season with salt and pepper and spread a layer of hummus over the entire chicken breast. Bake in the oven for 40 minutes at 180°C until the chicken is cooked through and the hummus is slightly crispy. I probably made my layer of hummus too thick and it was not crispy all the way through. It still tasted good and was a healthy, quick and cheap dinner.

Spinach feta hummus salad

  1. Laskaridis, K., Serafeimidou, A., Zlatanos, S., Gylou, E., Kontorepanidoub, E. and Angelos Sagredosc (2012). Changes in fatty acid profile of feta cheese including conjugated linoleic acid. J Sci Food Agric. 93: 2130-2136.
  2. Chin, S. F., Liu, W., Storkson, J. M., Ha, Y. L., Pariza, M. W. (1992). Dietary sources of conjugated dienoic isomers of linoleic acid, a newly recognised class of anticarcinogens. J Food Compos Anal. 5:185–97.
  3. Pariza, M. W. (2004). Perspective on the safety and effectiveness of conjugated linoleic acid. Am J Clin Nutr. 79(suppl):1132S–6S.
  4. Park, Y., Albright, K. J., Liu, W., Storkson, J. M., Cook, M. E., Pariza, M. W. (1997). Effect of conjugated linoleic acid on body composition in mice. Lipids. 32:853.
  5. West, D. B., Delany, J. P., Camet, P. M., Blohm, F., Truett, A. A. and Scimeca, J. (1998). Effects of conjugated linoleic acid on body fat and energy metabolism in the mouse. Am J Physiol. 275:R667–72.
  6. West, D. B., Blohm, F. Y., Truett, A. A. and Delany, J. P. (2000). Conjugated linoleic acid persistently increases total energy expenditure in AKR/J mice without increasing uncoupling protein gene expression. J Nutr. 130: 2471–7.
  7. de Deckere, E. A., van Amelsvoort, J. M., McNeill, G. P., Jones, P. (1999). Effects of conjugated linoleic acid (CLA) isomers on lipid levels and peroxisome proliferation in the hamster. Br J Nutr. 82:309 –17.
  8. Park, Y., Storkson, J. M., Albright, K. J., Liu, W., Pariza, M. W. (1999). Evidence that the trans-10,cis-12 isomer of conjugated linoleic acid induces body composition changes in mice. Lipids. 34:235– 41.
  9. den Hartigh, L., Han, C., Wang, S., Omer, M. and Chait, A. (2013). 10E,12Z-conjugated linoleic acid impairs adipocyte triglyceride storage by enhancing fatty acid oxidation, lipolysis, and mitochondrial reactive oxygen species. J. Lipid Res. 54: 2964-2978.
  10. Obsen, T., N. J. Faergeman, S. Chung, K. Martinez, S. Gobern, Loreau, M. Wabitsch, S. Mandrup and M. McIntosh. (2012). Trans-10, cis-12 conjugated linoleic acid decreases de novo lipid synthesis in human adipocytes. J. Nutr. Biochem. 23: 580–590.
  11. LaRosa, P. C., Riethoven, J. J., Chen, H., et al. (2007). Trans-10, cis-12 conjugated linoleic acid activates the integrated stress response pathway in adipocytes. Physiol Genomics. 31:544–53.
  12. Clement, L., Poirier, H., Niot, I., et al. (2002). Dietary trans-10,cis-12 conjugated linoleic acid induces hyperinsulinemia and fatty liver in the mouse. J Lipid Res. 43:1400–9.
  13. Ip, M. M., McGee, S. O., Masso-Welch, P. A, et al. (2007). The t10,c12 isomer of conjugated linoleic acid stimulates mammary tumorigenesis in transgenic mice over-expressing erbB2 in the mammary epithelium. Carcinogenesis. 28:1269–76.
  14. Meng, X., Shoemaker, S. F., McGee, S. O., Ip, M. M. (2008). t10,c12-Conjugated linoleic acid stimulates mammary tumor progression in Her2/ErbB2 mice through activation of both proliferative and survival pathways. Carcinogenesis. 29:1013–21.
  15. Belda, B. J., Thompson, J. T., Eser, P. O. and Vanden Heuvel, J. P. (2012). 10E12Z CLA alters adipocyte differentiation and adipocyte cytokine expression and induces macrophage proliferation. J Nutr Biochem. 23:510–8.
  16. Belda, B., Thompson, J., Sinha, R., Prabhu, K. and Vanden Heuvel, J. (2012). The dietary fatty acid 10E12Z-CLA induces epiregulin expression through COX-2 dependent PGF2a synthesis in adipocytes. Prostaglandins & other Lipid Mediators. 99: 30-37.
  17. Tholstrup, T., M. Raff, E. M. Straarup, P. Lund, S. Basu, and J. M. Bruun. (2008). An oil mixture with trans-10, cis-12 conjugated linoleic acid increases markers of inflammation and in vivo lipid peroxidation compared with cis-9, trans-11 conjugated linoleic acid in postmenopausal women. J. Nutr. 138:1445 – 1451.
  18. Whigham, L., Watras, A. and Schoeller, D. (2007). Efficacy of conjugated linoleic acid for reducing fat mass: a meta-analysis in humans. Am J Clin Nutr. 85: 1203-11.

One thought on “Spinach and feta hummus and does the scientific literature support the claims about conjugated linoleic acid and fat loss?

  1. Pingback: TECNOLOGÍA » Everything you always wanted to know about fermented foods « Science-Based Medicine

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