There are so many diets out there, all of them promise you the moon and the stars, but do any of them work? This blog will look at the two main low carb diets out there at the minute, the Atkins diet and the Keto diet.
First let’s look at the Atkins diet. The Atkins diet was created by Dr Robert C Atkins, a cardiologist. Since his book ‘Dr. Atkins’ Diet Revolution; was released in 1972 more than 16 million copies have been sold worldwide. The Atkins diet was very popular in the US, the UK, Scandinavia and surprisingly, Italy, which is well known for its pasta and pizza. It is a low carbohydrate diet usually recommended for people who need to lose weight. The diet is high in protein and fats, which fill you quicker than carbohydrates do, thus you tend not to consume as much food (i.e. less calories). Like I mentioned in my previous blog on Carbohydrates, no one nutrient is more responsible than another for weight gain, it is taking in more overall calories than you use up as energy. So, by consuming less food you consume less calories causing you to lose weight. The Atkins diet involves 4 phases;
Phase 1 – (Induction), during this phase you consume less than 20g of carbohydrates per day for 2 weeks. This should put your body in a state of Ketosis, Ketosis is when your body starts to burn fat for energy instead of carbohydrate due to carbohydrate intake being low.
Phase 2 (Balancing), slowly introduce more carbohydrates back into your diet in the form of nuts, low carbohydrate vegetables and small amounts of fruit.
Phase 3 (fine tuning), When you have almost reached you desired weight add more healthy carbohydrates back into your diet so weight loss will slow down.
Phase 4 (Maintenance), it’s exactly what it sounds like. You now have to maintain your ideal weight by staying away from all refined carbohydrates (white bread, white rice, white pasta, sugary foods etc), and eating as much healthy carbohydrates (wholegrains, fruit and vegetables) as your body can tolerate without gaining weight. This will be different from person to person depending on a number factors such as age, gender, activity level and metabolism. (Gunnars, 2018)
Studies have shown that the Atkins diet does promote weight loss in the majority of people, so it would be an effective weight loss plan for someone who was overweight or obese (Norhalila and Khadijah, 2016). There are a few factors that influence how effective the Atkins diet is for weight loss, these include;
Age – the younger you are the more effective the diet is for weight loss (Selner, 2016)
Gender – males tend to lose more weight on this diet than females because males usually have more lean muscle than females (Jf et al., 2008)
Water consumption – drinking water helps lose weight by kerbing hunger and boosting metabolism up to 3% ,will help in removing excess water weight and unwanted toxins which is also beneficial in reducing more weight (Norhalila and Khadijah, 2016).
Exercise – obviously if you add regular exercise weight loss will be more effective.
The main upside to using the Atkins diet for weight loss is that it is not very time consuming, no calorie counting is involved. It also doesn’t require you to buy ‘special’ food and drink, or to attend regular meetings (unlike some other weight loss programmes), so it is inexpensive to follow. It does however have some limitations. No white flour or refined carbohydrates are allowed, this can make it difficult when eating out or buying certain types of foods. You kind of need to make your food from scratch in order to follow the diet properly (Gunnars, 2018). Another thing to be aware of is that drastically cutting carbohydrates from your diet can result in early side effects such as;
Nutritional deficiencies caused by lack of fibre from wholegrains, this can cause constipation, diarrhoea and nausea
Side effects of Ketosis (from phase 1) can include mental fatigue (brain fog), nausea, headache and bad breath.
Dizziness, weakness and fatigue are some of the other possible side effects.
If you are Diabetic (type 1 or type 2 and on medication), or you take Diuretics you should consult with your doctor before attempting the Atkins diet. Also, if you are pregnant, breastfeeding or have Kidney disease this diet is not the one for you!
Now for the Ketogenic diet. The Ketogenic diet is a very low carb diet with moderate protein and high fat consumption. It is divided out with <10% overall calories coming from carbohydrates, 10-30% of calories from protein and 65-90% from fat (Feinman et al., 2015). This is what you would be aiming for in phase 1 of the Atkins diet, the very low carb phase that puts your body into a state of Ketosis. What is different about the Keto diet is that you stay in that phase, you don’t re-introduce good carbs into your diet like you do in the last phases of the Atkins diet. The goal of the Keto diet is to keep the body in a permanent state of Ketosis, so it burns fat to use it as an energy source instead of carbohydrate (Staverosky, 2016). It was first used as a treatment for children who had seizures (Liu et al., 2018). It is much more restrictive than the Atkins diet, and so can be extremely difficult to maintain. Like the different phases of the Atkins diet, there are different versions of the Keto diet.
The Standard Keto Diet (SKD) involves approximately 10% of your calories coming from carbs, 20% from protein and 70% from fat.
The High protein Keto Diet (HPKD) is like the SKD but it includes a larger percentage of protein. Typically, 5% carbs, 35% protein and 60% fat.
The Targeted Keto Diet (TKD) includes carbs around workouts and
The Cyclic Keto Diet (CKD) includes several low card ‘Keto’ days, and several high carb days. Example 5 Keto days and 2 high carb days.
The SKD and the HPKD are the types of Keto diet more commonly used as more research has been carried out on them. The CKD and the TKD are mainly only used by athletes and bodybuilders (Mawer, 2020). Studies have shown the Keto diet to be successful for weight loss, even more successful than a low fat diet (Bueno et al., 2013; Seid and Rosenbaum, 2019; Sumithran et al., 2013). The Keto diet has also shown to be effective in increasing insulin sensitivity, in one study by up to 75% (Boden et al., 2005). Low insulin sensitivity leads to developing Type 2 Diabetes. Weight loss will also help lower your risk of developing type 2 Diabetes. However, if you already have type 2 Diabetes and are on medication called sodium-glucose cotransporter 2 (SGLT2) inhibitors for it the Keto diet could cause you to develop a life-threatening illness called Diabetic Ketoacidosis where your blood becomes acidic (H et al., 2017). Early side effects of the Keto diet are the same as the Atkins diet. Away off possibly minimising these symptoms may be to slowly wean yourself off carbohydrates. Another thing to be mindful of is what it initially feels like when your body is in Ketosis. You will have increased thirst, increased urination, dry mouth and decreased appetite (the last one is probably what you want if you are looking to lose weight…but the other 3 aren’t so pleasant) (Bostock et al., 2020). Some Health risks for staying on the Keto diet long-term include;
Low protein in the blood
Extra fat in the liver which can cause liver inflammation. This can damage your liver and create scarring. In serious cases this can result in liver failure.
Developing kidney stones
Micronutrient (vitamins & minerals) deficiencies
Some similarities and differences between the Atkins and the Keto Diet are;
| Similarities | Differences |
| Both are low carbohydrate diets | The Keto diet is a moderate protein diet (around 205 of overall calories from protein). Atkins is higher in protein (up to 30% of calories from protein) |
| Both have been proven to promote weight loss | On the Keto body you stay in ketosis by limiting your carbohydrate consumption the whole time. In the Atkins diet you gradually re-introduce healthy carbohydrates back into your diet you’re your weight loss goal is achieved. |
| Phase 1 of the Atkins diet restricts carbs to cause Ketosis | The Atkins diet is more flexible than the Keto diet, and easier to maintain |
Now we’re going to look at another version of the Atkins Diet called the Modified Atkins Diet, it’s MAD (sorry, I couldn’t help myself!). The MAD has been used since 2003 to treat children and adults with refractory Epilepsy. It is halfway between the Keto diet and the Atkins Diet regrading how much Carbs are allowed (more carbs than the Keto, but less than the traditional Atkins). It’s not as strict as the Keto diet because there’s no fluid or calorie limitations. Fat is strongly encouraged. There are no protein restrictions. Foods are not weighed or measured, but carbohydrates are counted. This diet wouldn’t be classed as a ‘weight loss’ diet. Studies have shown a 50% reduction in seizures after 6 months following this diet (Schachter, 2020).
Overall, studies have shown health benefits associated with a low carbohydrate diet. Weight loss is the main one with the Atkins diet resulting in desired weight loss 6-12 months after starting the diet (Anton et al., 2017). Ketosis, which occurs in both the Atkins diet and the Keto diet, reduces appetite which also aids with weight loss. The Keto diet preserves muscle mass so any weight loss is mainly down to fat mass lost (Moreno et al., 2014). Blood sugar control is another health benefit both the Atkins and the Keto diet seem to have (Boden et al., 2005). For type 2 Diabetics who are not on sodium-glucose cotransporter 2 (SGLT2) a low carb diet can help reduce how much diabetes medication is required and improve hbA1c levels (Tay et al., 2015; Saslow et al., 2017).
I must admit, when it comes to these kinds of diets which single out one specific nutrient (in this case carbohydrates) as a ‘baddy’ I’m not a big fan. Obviously in certain circumstances when that type of diet helps treat a specific illness, such as with the Modified Atkins Diet for treating Epilepsy, it is fine. From my research I feel that for people who are very overweight and for their own health need to lose weight fast going on the Atkins diet which will allow them to reintroduce healthy carbohydrates once they have reached a healthy weight sounds better to me. I just don’t feel that a diet which has some pretty nasty risks associated with it if you follow it long term can be good for you, and let’s face it, if you do lose weight on the Keto diet (which you likely will), you will probably be a bit uneasy about coming of it and eating normally again in case you gain weight. However, nutrition is a very individual thin. Thousands of studies can be done to give a broad idea of whether something is good or bad for us, but something that is harmful to one person’s health could be very beneficial for another’s! If you want to try these diets research them so that you are aware of any risks involved. Talk with your doctor if you have any queries or concerns, and most importantly, listen to your own body! If you are feeling terrible and you don’t feel like the diet is benefiting you it probably isn’t for you.
References
Anton, S.D., Hida, A., Heekin, K., Sowalsky, K., Karabetian, C., Mutchie, H., Leeuwenburgh, C., Manini, T.M. and Barnett, T.E. (2017) Effects of Popular Diets without Specific Calorie Targets on Weight Loss Outcomes: Systematic Review of Findings from Clinical Trials. Nutrients, 9(8).
Boden, G., Sargrad, K., Homko, C., Mozzoli, M. and Stein, T.P. (2005) Effect of a low-carbohydrate diet on appetite, blood glucose levels, and insulin resistance in obese patients with type 2 diabetes. Annals of Internal Medicine, 142(6) 403–411.
Bostock, E.C.S., Kirkby, K.C., Taylor, B.V. and Hawrelak, J.A. (2020) Consumer Reports of ‘Keto Flu’ Associated With the Ketogenic Diet. Frontiers in Nutrition, 7. Available from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7082414/ [accessed 8 January 2021].
Bueno, N.B., de Melo, I.S.V., de Oliveira, S.L. and da Rocha Ataide, T. (2013) Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. The British Journal of Nutrition, 110(7) 1178–1187.
Feinman, R.D., Pogozelski, W.K., Astrup, A., Bernstein, R.K., Fine, E.J., Westman, E.C., Accurso, A., Frassetto, L., Gower, B.A., McFarlane, S.I., Nielsen, J.V., Krarup, T., Saslow, L., Roth, K.S., Vernon, M.C., Volek, J.S., Wilshire, G.B., Dahlqvist, A., Sundberg, R., Childers, A., Morrison, K., Manninen, A.H., Dashti, H.M., Wood, R.J., Wortman, J. and Worm, N. (2015) Dietary carbohydrate restriction as the first approach in diabetes management: critical review and evidence base. Nutrition (Burbank, Los Angeles County, Calif.), 31(1) 1–13.
Gunnars, K.Bs. (2018) The Atkins Diet: Everything You Need to Know Available from https://www.healthline.com/nutrition/atkins-diet-101 [accessed 4 January 2021].
H, Q., A, N. and V, V. (2017) Ketosis and diabetic ketoacidosis in response to SGLT2 inhibitors: Basic mechanisms and therapeutic perspectives Available from https://pubmed.ncbi.nlm.nih.gov/28099783/ [accessed 8 January 2021].
Jf, H., Cm, G., Vj, S., Pj, B., Lj, A., Jd, A., Cm, C., A, D., Tp, E., K, F., D, L., Ph, L., Cm, L., C, S.-H., Wm, V., Lp, S. and undefined (2008) Weight loss during the intensive intervention phase of the weight-loss maintenance trial. American Journal of Preventive Medicine, 35(2) 118–126. Available from http://europepmc.org/article/MED/18617080 [accessed 4 January 2021].
Liu, H., Yang, Y., Wang, Y., Tang, H., Zhang, F., Zhang, Y. and Zhao, Y. (2018) Ketogenic diet for treatment of intractable epilepsy in adults: A meta-analysis of observational studies. Epilepsia Open, 3(1) 9–17.
Mawer, R. (2020) The Ketogenic Diet: A Detailed Beginner’s Guide to Keto Available from https://www.healthline.com/nutrition/ketogenic-diet-101 [accessed 8 January 2021].
Moreno, B., Bellido, D., Sajoux, I., Goday, A., Saavedra, D., Crujeiras, A.B. and Casanueva, F.F. (2014) Comparison of a very low-calorie-ketogenic diet with a standard low-calorie diet in the treatment of obesity. Endocrine, 47(3) 793–805.
Norhalila, C.C.M. and Khadijah, S.J. (2016) Weight Loss with Atkins Diet. In: Eminent Association of Pioneers (EAP) August 22-24, 2016 Kuala Lumpur (Malaysia). 22 August 2016 Eminent Association of Pioneers (EAP),.
Saslow, L.R., Daubenmier, J.J., Moskowitz, J.T., Kim, S., Murphy, E.J., Phinney, S.D., Ploutz-Snyder, R., Goldman, V., Cox, R.M., Mason, A.E., Moran, P. and Hecht, F.M. (2017) Twelve-month outcomes of a randomized trial of a moderate-carbohydrate versus very low-carbohydrate diet in overweight adults with type 2 diabetes mellitus or prediabetes. Nutrition & Diabetes, 7(12) 304.
Schachter, Steven.C. (2020) Modified Atkins Diet Available from https://www.epilepsy.com/learn/treating-seizures-and-epilepsy/dietary-therapies/modified-atkins-diet [accessed 4 January 2021].
Seid, H. and Rosenbaum, M. (2019) Low Carbohydrate and Low-Fat Diets: What We Don’t Know and Why We Should Know It. Nutrients, 11(11). Available from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6893678/ [accessed 8 January 2021].
Selner, M. (2016) Weight Loss and Age Available from https://www.healthline.com/health/weight-loss-and-age [accessed 4 January 2021].
Staverosky, T. (2016) Ketogenic Weight Loss: The Lowering of Insulin Levels Is the Sleeping Giant in Patient Care. The Journal of medical practice management: MPM, 32(1) 63–66.
Sumithran, P., Prendergast, L.A., Delbridge, E., Purcell, K., Shulkes, A., Kriketos, A. and Proietto, J. (2013) Ketosis and appetite-mediating nutrients and hormones after weight loss. European Journal of Clinical Nutrition, 67(7) 759–764.
Tay, J., Luscombe-Marsh, N.D., Thompson, C.H., Noakes, M., Buckley, J.D., Wittert, G.A., Yancy, W.S. and Brinkworth, G.D. (2015) Comparison of low- and high-carbohydrate diets for type 2 diabetes management: a randomized trial. The American Journal of Clinical Nutrition, 102(4) 780–790.
