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Diets that do and diets that don’t: Part 4 – The Dukan Diet

By Tamzyn Murphy

BSc Med(Hons) Human Nutrition and Dietetics, RD

 

Unlike the typical low carb diet, Dukan is high in protein (starting at 40% of calories) and low in fat (20% of calories). It’s big on rules and the restrictive phases are incredibly strict – any indiscretion is seen as a major failure. The idea is to replace much of your dietary carbs and fat with protein, which is filling, low in calories and takes time and work to digest. Studies on low carb, low fat, high protein diets show that you’ll naturally eat far fewer calories, feel full and you’ll likely experience metabolic benefits, including improved cholesterol, blood fat, glucose and insulin levels, thereby possibly reducing heart disease, diabetes and metabolic syndrome risk.[i], [ii] But weight loss benefits don’t appear to out-do other diets.

There are four phases. Phase one lasts about 5 days and consists almost exclusively of protein food – meat, seafood, poultry, eggs, vegetable-protein and fat-free dairy. No vegetables. Phase two allows non-starchy veg to be added to phase one’s protein foods, on every alternate day, and continues until you’ve lost the weight. The third phase last a few months and allows all the protein food and non-starchy veg you like, as well as limited fruit, whole grain bread and cheese. Phase three also allows two starch servings (e.g. pasta) and two anything-you-want meals each week. Phase four: eat what you like six days of the week, bearing in mind what you learnt during phase 3. On day seven you must eat like you did in phase one. A daily oat bran serving forms part of each phase, probably in an attempt to increase the fibre content of the diet.

Dukan’s excessive protein may increase your risk of gout[iii] and put strain on the kidneys[iv]. And a high protein and low fibre diet is bound to give you constipation. Cutting out entire food groups may put you at risk for nutritional deficiencies. So if you’re insistent on following this diet, it’s probably prudent to take a complete vitamin and mineral supplement, especially during the first two very restrictive phases. Phase four’s sudden dietary freedom may leave you directionless and reverting back to your old ways, resulting in rebound weight gain. And with all the expensive protein you’re guzzling, prepare for dent in your bank balance; as well as a conscience-prick at the number of animals that are being killed and the environmental impact of a carnivorous diet.

References

[i] Dumesnil JG, Turgeon J, et al. Effect of a low-glycaemic index–low-fat–high protein diet on the atherogenic metabolic risk profile of abdominally obese men. British Journal of Nutrition. Nov 2001;86(5):557-68 

[ii] Farnsworth E, Luscombe ND, et al. Effect of a high-protein, energy-restricted diet on body composition, glycemic control, and lipid concentrations in overweight and obese hyperinsulinemic men and women.

[iii] Torralba KD, De Jesus E, Rachabattula S. The interplay between diet, urate transporters and the risk for gout and hyperuricemia: current and future directions. Int J Rheum Dis. 2012 Dec;15(6):499-506 

[iv] Juraschek SP, Appel LJ, et al. Effect of a high-protein diet on kidney function in healthy adults: results from the OmniHeart trial. Am J Kidney Dis. 2013 Apr;61(4):547-54

Inflammatory food

Excess inflammation leads to autoimmune, inflammatory and age-related diseases as well as aging, but changing the way you eat can help

By Tamzyn Murphy Campbell
BSc, BSc Med(Hons) Human Nutrition and Dietetics, RD

Excess inflammation leads to autoimmune, inflammatory and age-related diseases as well as aging, but changing the way you eat can help

By Tamzyn Murphy Campbell
BSc, BSc Med(Hons) Human Nutrition and Dietetics, RD

To most of us “inflammation” – characterised by redness, heat, pain and swelling – is a dreaded word associated with a variety of ailments: joint pain, backache, arthritis, inflammatory bowel disease and psoriasis (skin condition). But inflammation actually has an essential role to play. It’s our body’s first form of attack against infection or other foreign bodies. The wellknown inflammation related problems set in when inflammation spirals out of control and starts to attack the body’s own tissues – autoimmune disease – or when it goes on too long – thought to be one of the processes responsible for aging and related diseases. So, although inflammation is an important indicator of something being wrong, keeping it in check and preventing it from going overboard is fundamental to health – and what you eat can help.

BEAT THE BELLY

Belly fat releases inflammatory molecules which scientists blame for obesity-associated inflammatory diseases: insulin resistance, diabetes and heart disease risk factors (high blood pressure and imbalanced blood fat and cholesterol levels). It’s also linked to lower levels of the hormone adiponectin, which may play a role in increased inflammation, heart disease risk and insulin resistance. Research indicates that women with a belly have more signs of inflammation than their male counterparts. Scientists have found that using diet to keep weight in check reduces inflammation and the markers of its associated diseases. So find a diet and exercise program that works for you, and stick to it to drop the kilos and keep inflammation free. Reducing stress and getting adequate sleep can also help keep the belly at bay.

INFLAMMATORY FOOD

Researchers have found that certain food promotes inflammation, while other food reduces it. Avoid the following to reduce inflammation:

  • Trans fats – found in processed baked goods (biscuits) and fast food fried in reused oil – raise inflammation-boosting molecules and heart disease risk
  • Refined carbohydrates and sugar increase inflammation, probably due to the combination of their low fibre, vitamin, mineral, phytonutrient and essential fatty acid content, as well as their penchant for swinging blood sugar and insulin levels. This boosts blood fat and free radicals, causing inflammatory molecule production, which in turn results in inflammation
  • Processed food is high in trans fats and refined carbohydrates and sugar. So they’re definitely a no-no
  • Excess omega-6 fats Most of us get too much inflammation-promoting omega-6 in our diet, from processed food and cooking oils, like sunflower oil. The omega-6 fat, linoleic acid (LA) is converted into arachidonic acid (AA), which is the major building block for making inflammation-promoting molecules (eicosanoids).

ANTI-INFLAMMATORY FOOD

This food helps reduce inflammation throughout the body and therefore also age-related inflammatory diseases (e.g. osteoarthritis) and the activation of aging genes

  • Unsaturated fats Monounsaturated fats from nuts, seeds, avocado, olive and canola oils improve your blood fat profile to reduce inflammatory molecules and heart disease risk
  • Omega-3 fats found in oily fish (Norwegian salmon, snoek, sardines, anchovies), activate anti-inflammation genes. They’re also a building block for the production of anti-inflammatory molecules. And higher levels of omega-3 fats inhibit the production of inflammatory molecules made from omega-6 fats. Eat fatty fish at least three times per week or supplement with fish, or krill oil
  • Moderate alcohol has been linked to lower blood levels of inflammation-promoting molecules and reduced heart disease risk. Wine (1-2 glasses daily) is particularly anti-inflammatory, but beer and liquor have also been found to be beneficial
  • Antioxidants found in fruit and vegetables (especially brightly coloured ones), certain herbs and spices (cloves, oregano, rosemary, tumeric), green and rooibos tea, dark chocolate and red wine reduce free radical damage and inflammatory molecule production
  • Fibre exerts its anti-inflammatory effects by helping control blood sugar, insulin, fat and cholesterol levels, increasing adiponectin levels and reducing inflammatory molecule production. Fibre’s found in vegetables, fruit, beans, lentils, nuts and seeds.

References include

  1. Chung HY, Lee EK, et al. Molecular Inflammation as an Underlying Mechanism of the Aging Process and Age-related Diseases. JDR. Jul 2011;90(7):830-40
  2. Pou KM, Massaro JM, et al. Visceral and subcutaneous adipose tissue volumes are cross-sectionally related to markers of inflammation and oxidative stress. The Framingham Heart Study. Circulation. 2007;116:1234-41
  3. Giugliano D, Ceriello A, et al. The effects of diet on inflammation. Journal of the American College of Cardiology. 2006;48(4):677-85
  4. Lihn AS, Pedersen SB, Richelsen B. Adiponectin: action, regulation and association to insulin sensitivity. Obes Rev. Feb 2005;6(1):13-21
  5. Tajik N, Keshavarz SA, et al. Effect of diet-induced weight loss on inflammatory cytokines in obese women. J Endocrinol Invest. Jun 2012: Published online
  6. Calder PC. n−3 Polyunsaturated fatty acids, inflammation, and inflammatory diseases. Am J Clin Nutr. Jun 2006;83(6):S1505-19
  7. ORAC Values. www.oracvalues.com. Jul 2012