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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

Side effects of low carbohydrate high fat (LCHF) eating

By Tamzyn Murphy Campbell

BSc, BSc Med(Hons) Human Nutrition and Dietetics, RD

 

Many people experience certain common side effects when following low carbohydrate high fat (LCHF). These include:

  1. Keto “flu”: during the first week of starting LCHF some people experience aches and pains, headaches, lethargy, nausea, brain fog and/or irritability.
  2. Constipation
  3. Fatigue/lethargy
  4. Muscle aches/cramps
  5. Headaches
  6. Signs of low blood pressure, including heart palpitations, dizziness and nausea.

The good news is that the root cause of these symptoms is the same and completely rectifiable.

 

What’s behind the symptoms?

When you are eating a conventional high carbohydrate diet, your body is producing quite a lot of insulin. Insulin is produced by the pancreatic beta cells in response to glucose or “sugar” entering the bloodstream after digestion of a carbohydrate-containing food or beverage. Insulin’s job is to remove “sugar” from the bloodstream and put it into the cells, where it’s turned into energy or stored. One of the side effects of insulin is to reduce the kidneys’ excretion of water and certain electrolytes or minerals (namely, sodium or ‘salt’, magnesium and potassium) [1-3].

Conversely, when you eat a low carbohydrate diet the amount of insulin that your pancreas produces is dramatically reduced, as there’s much less carbohydrate entering the blood stream from your diet. The lower insulin level results in increased excretion of water, sodium, magnesium and potassium from the kidneys.  This loss of fluid often lowers blood pressure and can cause dehydration if the fluid is not replaced by drinking more. The resulting symptoms can include headaches and symptoms of low blood pressure, including fatigue/lethargy, heart palpitations, dizziness and nausea. The loss of sodium, potassium and magnesium can cause muscle aches, pains and cramps, as well as irritability. [1]

 

How to fix it

  1. Drink plenty of fluids (to thirst)
  2. Add salt to your food
  3. Drink a cup of bone broth every day
  4. Take a magnesium supplement, which provides 400 mg of elemental magnesium daily. Choose a supplement that contains magnesium in the form of a magnesium chelate (elemental magnesium bound to an amino acid), such as magnesium glycinate, for optimal absorption.

 

Important note: Should drinking more fluids, consuming more salt, drinking bone broth and taking a magnesium supplement not improve your symptoms, it is important that you see your doctor as soon as possible.

 

References

  1. Volek JS and Phinney SD. The art and science of low carbohydrate living. 2011
  2. DeFronzo RA. The effect of insulin on renal sodium metabolism. A review with clinical implications. 1981 Sep;21(3):165-71.
  3. Quiñones-Galvan A, Ferrannini E. Renal effects of insulin in man. J Nephrol. 1997 Jul-Aug;10(4):188-91.