Preparing legumes to maximise nutrition and minimise adverse effects

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By Tamzyn Murphy

BSc Med(Hons) Human Nutrition and Dietetics, RD

 

Legumes (peas, beans, lentils and peanuts) contain pesky and destructive anti-nutrients, which bind to other nutrients in food, inhibiting their absorption. Anti-nutrients also irritate the gut-lining, causing stomach trouble and making the gut ‘leaky’ – allowing proteins and other-usually ‘banned’ components through the gut wall and into the bloodstream. This may result in immune system problems including inflammation and possibly even autoimmune diseases.

 

However, legumes (especially soya) are great proteins sources for vegetarians, and even more so for vegans. They’re also a good source of fibre, B vitamins and other micronutrients. In order to reap legumes’ nutritional rewards without incurring the destructive health effects wreaked by their anti-nutrients you have to prepare them right.

A. Soak, sprout, cook, grind and ferment: The best way to do away with pesky anti-nutrients.

  1. Soak:
    • Cover dry legumes with warm water, acidified with vinegar or lemon juice, in a glass jar.
    • Cover the jar’s opening with a clean cloth secured with a rubber band.
    • Place the jar in a warm location for 12-24 hours.
    • Drain water out through the cloth and then rinse the legumes and drain again.
  1. Sprout
    • Store the damp legumes in a dark place (e.g. cupboard). Ensure the jar is on its side. Elevate the base slightly using a rolled-up or folded dish cloth. Place paper towels or a dishcloth beneath the cloth-covered side of the jar to allow the remaining water to drain out.
    • Rinse and drain the legumes twice a day.
    • Allow them to sprout (germinate) for a total of 3-5 days.
  1. Cook (boil) (optional/preferable)
    • Place legumes in pot.
    • Cover with water.
    • Bring to the boil on high heat.
    • Once boiling, turn heat down to low and allow to simmer for at least one hour. Ideally you can leave them to cook all day in a slow cooker.
  1. Grind, mash or break (optional/preferable)
    • Use a blender or food processor or mash (if cooked)
  2. Ferment
    • Add a powdered starter culture (as directed) or kefir (about one tablespoon culture per one cup of legumes) to the damp legumes in the jar. Seal the jar with a tight-fitting lid this time.
    • Allow the legumes to ferment for several days.
    • The jar needs to be ‘burped’ (briefly opened to release gases) daily. A protruding lid indicates that too much gas is building up, which needs releasing.

 

B. Soak properly and cook thoroughly: An abbreviated version that’s not as effective as the process above, but still inactivates most of the anti-nutrients.

  1. Soak:
    1. Soak dry legumes in warm water, acidified with vinegar or lemon juice, for 12 hours (preferably in a warm location)
  2. Drain legumes (discard water)
  3. Rinse legumes
  4. Repeat steps a, b and c twice (totalling 36 hours of soaking time)
  5. Boil legumes: Follow A.3. above
  6. Ferment (optional)
  7. Follow A.5. above. However, before fermenting it is essential to ensure that you break the skins by mashing or exerting enough downward pressure on the legumes to just break them.

 

References:

  1. Food & Wine. Step-by-step guide to Sprouting beans at home. http://www.foodandwine.com/slideshows/sprouting-beans#!slide=4
  2. Cultures for health. Fermenting beans and legumes. http://www.culturesforhealth.com/fermenting-beans-legumes
  3. Guyenet S. Traditional preparation methods improve grains’ nutritive value. 4 May 2010 http://wholehealthsource.blogspot.com/2010/05/traditional-preparation-methods-improve.html
  4. Nagel R. Living with phytic acid. The Weston A Price Foundation. 26 Mar 2010. http://www.westonaprice.org/health-topics/living-with-phytic-acid/

Can kids ‘Bant’?

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By Tamzyn Murphy

BSc Med(Hons) Human Nutrition and Dietetics, RD

 

We await the verdict of Prof Tim Noakes’ HPCSA trial over a tweet in which he “advised” a mother to wean her child onto LCHF food. In the meantime let’s take a closer look at the evidence regarding Banting and kids…

 

Today’s children are the first generation expected to live shorter lives than their parents [1]. We are seeing more overweight children and adolescents than ever before [2, 3]. And we know that overweight children are likely to grow up into overweight adults, with associated health risks (e.g. heart disease and diabetes) [4]. It is clear that the way most children are eating is not doing their health any favours.

 

If we always do what we’ve always done, we’ll always get what we’ve always got

 

Sickly sweet South African kids

Eating too much sugar is associated with dental caries and increased obesity risk [3]. Both of which are prevalent health concerns amongst South African children.

 

We know that children and adolescents in South Africa, and across the globe, eat more sugar than adults. In fact one study reported that South African children eat about 50g (12.5 teaspoons) of sugar each day, while South African adolescents consume as much as 100g (25 teaspoons) per day [3]. This represents 10-20% of daily calorie consumption [3]. South African adults on the other hand, are thought to be eating approximately 38-51g (9-13 teaspoons) of sugar each day, contributing 10-15% of their calories [3].  The World Health Organisation’s guidelines recommend a maximum of 5% of daily calories from sugar – that’s no more than 7 teaspoons daily from all sources. Reducing or even eliminating our children’s added sugar consumption can only be good for their health.

 

Most medical practitioners and scientists will agree that drastically reducing or even cutting out children’s sources of added sugar can only be good for them. But the question remains, can children safely following a low carbohydrate, high fat (LCHF) diet (popularly known as Banting in South Africa), that’s devoid of starches and wholegrains as well as sugar?

 

Evidence: very LCHF diets in children

Although, very little research has been done on LCHF eating in children, a few studies have shown that overweight  kids and teens (6-18 years of age) who followed a LCHF, containing less than 60g of carbs each day, successfully lost weight, without negatively affecting the levels of fat and cholesterol in their blood [5, 6]. The authors suggest that reducing dietary carbohydrate may be a possible treatment for insulin resistance in children and adolescents.

 

Of note, a very low carbohydrate, ketogenic diet has been successfully used to treat childhood epilepsy for almost a century [7]. A modified version of the Atkin’s diet, also very low in carbohydrates (it only contains 10g), but easier to follow than the ketogenic diet (as, unlike the ketogenic diet it doesn’t also limit calories and protein), has been used successfully for the same purpose for over a decade. Unlike protein and certain fats, dietary carbohydrates are not essential nutrients – our bodies can make them from scratch to use as fuel. So it’s not surprising that both the ketogenic and modified Atkin’s (probably more so than the ketogenic diet, which also limits protein and calories) diets are considered safe when used in conjunction with multivitamin and calcium supplementation [8, 9].

 

“Banting” for children needn’t be very low carb

It’s important to bear in mind that most children who follow a LCHF don’t need to drastically restrict carbohydrates to the ketogenic levels (<60g per day) investigated in the studies discussed above (A LCHF diet typically provides 20-120g of carbohydrate daily or 5-30% of total energy intake). So, while added sugar, starches and grains will be eliminated from their diets, other wholefood sources of carbohydrates won’t be excluded (e.g. dairy, starchy vegetables, nuts, seeds, fruit and even properly prepared legumes).  I recommend that children only restrict their carbohydrates to below 60g under the supervision of a dietitian or knowledgeable medical doctor.

 

Provided that a child consumes the recommended 3 portions of dairy daily and eats enough vegetables, supplementation shouldn’t be any more necessary on this diet than with any other. While I don’t suggest being too restrictive about children’s starchy vegetable, fruit and nut consumption, excluding starches (in the form of grains) and added sugar from children’s diets shouldn’t pose any health risk and will likely come with a host of benefits. Especially considering that these restrictions are done in the context of a diet that emphasises avoiding processed food, while eating REAL, nutrient dense foods.

 

“Banting” for kids simplified

  • Eat real food. Avoid processed food.
  • Eat freely: Avocados, olives, other vegetables, dairy, fish, poultry, meat (including organ meats), eggs, butter, olive oil, coconut oil
  • Eat moderate amounts: Fruit, nuts, seeds, properly prepared legumes (beans, peas, lentils)
  • Exclude: Added sugar (in all its forms), processed food, grains (although it’s likely fine to include limited amounts of the less irritating grains such as oats or quinoa)

 

References 

[1] Olshsky SJ, Passaro DJ, Hershow RC, et al. A Potential Decline in Life Expectancy in the United States in the 21st Century. N Engl J Med 2005; 352:1138-1145 

[2] Gupta N, Goel K, Shah P, Misra A. Childhood Obesity in Developing Countries: Epidemiology, Determinants, and Prevention. Endocrine Reviews. Jan 2012;33(1) 

[3] Steyn N, Temple NJ et al. Evidence to support a food-based dietary guideline on sugar consumption in South Africa. BMC Public Health. 2012;12:502

[4] Singh AS, Mulder C, Twisk JWR, et al. Tracking of childhood overweight into adulthood: a systematic review of the literature. Obesity Reviews. Sep 2008;9(5):474-88 

[5] Gow ML, Ho M, Burrows TL, et al. Impact of dietary macronutrient distribution on BMI and cardiometabolic outcomes in overweight and obesechildren and adolescents: a systematic review. Nutr Rev. 2014 Jul;72(7):453-70. 

[6] Sondike SB, Copperman N, Jacobson MS. Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. J Pediatr. 2003 Mar;142(3):253-8. 

[7] NICUS. The Ketogenic Diet…Fa(c)t or fiction? 2007

[8] Tonekaboni SH, Mostaghimi P, Mirmiran P, et al. Efficacy of the Atkins diet as therapy for intractable epilepsy in children. Arch Iran Med. 2010 Nov;13(6):492-7. 

[9] Suo C, Liao J, Lu X, et al. Efficacy and safety of the ketogenic diet in Chinese children. Seizure. 2013 Apr;22(3):174-8. 

Best first food for baby: Meat vs cereal

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By Tamzyn Murphy

BSc Med(Hons) Human Nutrition and Dietetics, RD

 

South African personality, sports scientist and Emeritus UCT Professor Tim Noakes is making news headlines again as the second and last day of the closing arguments of his “Baby Banting” trial before the Health Professions Council of South Africa (HPCSA) commences. The council is investigating Noakes for giving unconventional and un professional advice. The complaint laid by Association for Dietetics (ADSA) president, Claire Julsing-Strydom, is over ‘advice’ that Noakes tweeted in response to a mother’s query regarding the best food to introduce to her baby. Noakes advised the mother to introduce low carbohydrate, high fat (LCHF), Banting-friendly foods (which include meat and vegetables) to her baby from 6-month of age.

While the HPCSA will determine whether babies should or shouldn’t Bant, it is clear that Noakes is right about at least one thing: meat is far superior to cereal as babies’ first food. Health authorities’ recommendations that meat, meat alternatives (like eggs) and iron-fortified cereal are the best first food for babies imply that these are options are nutritional equals [1]. They are not. Here’s why meat beats cereal hands down.

 

Meating babies’ nutritional needs

Iron deficiency is very common in children in South Africa [2,3], and across the globe [4]. Many infants also don’t eat enough iron [2]. Infants with iron deficiency have impaired growth, mental development and problem solving ability [4]. Iron deficient babies score worse for mental and motor functioning when they’re older too [4]. By 6 months of age babies run out of iron stores [4]. Meat, fish and poultry are rich sources of the most readily absorbed heme form of iron. The iron contained in iron fortified cereal on the other hand, is in a non-haem form that is very poorly absorbed [4].

Meat, liver, poultry and fish – given as babies’ first foods in many traditional societies [1] – were the obvious iron-rich first foods to be introduced to babies before iron-fortified cereals were available. Since iron-fortified cereal was introduced it has replaced meat as the first food of choice for babies [4]. Not only is it a poor replacement as a source of bioavailable iron, but it also contains anti-nutrient phytates, which interfere with iron absorption, thereby reducing its bioavailability even further [2]. Therefore, cereal, even if it’s fortified with iron, may not be able to provide the iron that 6 month olds so desperately need.

Interestingly, zinc deficiency is also very common in babies and children. Meat is an excellent source of zinc. Introduction of meat as opposed to cereal as an early complementary food for exclusively breastfed infants is associated with improved zinc, iron and protein intake.  Babies fed meat instead of cereal have a higher head circumference and possibly also improved psychomotor development [5].

 

A weighty issue

Dietitian text books recommend that sugar and salt are not added to babies foods. Yet in the same breath they say that fortified infant cereal – usually packed with added sugar – is the first food to be introduced to babies [4].

Dietary sugar is linked to dental caries and the development of obesity and other lifestyle-related diseases. Even if parents do find baby cereal options that don’t include added sugar, they are still very refined (processed) and incredibly high in fast-release (high GI) carbohydrates.

Introducing cereals and fruit as babies’ first solid food is linked to the development obesity later in life [6]. Meat contains no carbohydrate and is high in fat and protein. A high fat intake during babies’ complementary feeding period doesn’t appear to increase their risk of becoming obese later [7]. There has been concern that high protein intake during infancy promotes weight and fat gain. However, a recent study indicates that this only holds true for high levels of protein from cow’s milk in formula fed infants. Breastfed babies who were fed meat instead of cereal, gained more weight and grew taller than those fed cereal, but they didn’t get fatter [8]. This indicates that higher protein levels from meat may not be linked to fatness after all.

Parents and health professionals await the outcome of Noakes’ HPCSA trial with bated breath. For now though, at least one aspect is clear: introducing ‘Banting-friendly’ meat to babies is a far better option than introducing cereal. From 6 months of age, babies should be offered pureed meat, liver, poultry, fish and eggs, progressing to the introduction of a variety of foods from family meals, such as vegetables mixed with pasture-fed butter, olive oil or breastmilk. Breastmilk continues to be the main source of nutrition throughout the first year. Breastfeeding is recommended for at least one year whenever possible, and preferably for up to two years or beyond.

 

References

[1] Health Canada. Nutrition for health term infants: Recommendations from six to 24 months. 24 Mar 2014

[2] Faber M, Wenhold F. Nutrition in contemporary South Africa. AJOL. 2007;33(3):393-400

[3] Visser J, Herselman M. Anaemia in South Africa: the past, the present and the future. S Afr J Clin Nutr. 2013;26(4):166-167

[4] Mahan LK, Escott-Stump S. Krause’s Food & Nutrition Therapy. International Edition 12. Saunders Elsevier. 2008

[5] Krebs NF, JE Wescott, N Butler, et al. Meat as a First Complementary Food for Breastfed Infants: Feasibility and Impact on Zinc Intake and Status. J Pediatr Gastroenterol Nutr. Feb 2006;42(2)

[6] Caroli M, Mele RM, Tomaselli MA, et al. Complementary feeding patterns in Europe with a special focus on Italy. Nutr Metab Cardiovasc Dis. Oct 2012;22(10):813-8

[7] Michaelsen KF, Larnkjaer A, Molgaard C. Early diet, insulin-like growth factor-1, growth and later obesity. World Rev Nutr Diet. 2013;106:113-8

[8] Tang M, Krebs NF. High protein intake from meat as complementary food increases growth but not adiposity in breastfed infants: a randomized trial. Am J Clin Nutr. Oct 2014;ajcn.088807

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

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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