Here we go! Two more popular diets, broken down.
The Paleolithic diet, aka Paleo diet, is set up to mimic the food habits of humans from the Paleolithic Era (45,000 to 10,000 BC)(Seema & Hafiz, 2017). This diet claims to be “designed by mother nature’s wisdom acting through evolution and natural selection” (Knappenberger, 2018).
The Paleo diet is alkalogenic, or puts the body in an alkaline state, to keep extracellular pH neutral, keeping the body in homeostasis. This state is said to improve diseases and symptoms of acid/base imbalance, such as inflammatory diseases, autoimmune disorders, and certain cancers (Seema & Hafiz, 2017, Knappenberger, 2018). It claims that the high soluble fiber intake will improve most diseases of the GI tract, and high omega-3 fat intake will improve most inflammatory diseases (Knappenberger, 2018).
Diet protocols: (Knappenberger, 2018)
Some protocols to following the diet include: only eating when hungry, no over exercising, getting eight hours of sleep, and supplementing with vitamin D and probiotics.
- Cereal grains
- Potatoes (sweet potatoes are ok)
- All added sugar, soft drinks, packaged sweets, juices
- Dairy (except butter and heavy cream)
- Red meat, poultry, organ meat, fish, shellfish, eggs
- Coconut oil, butter, beef tallow, lard, duck fat, olive oil, avocado oil
- Fresh or frozen vegetables (cooked or raw)
- Small amounts of fruits and nuts
In the beginning, the Paleo diet may promote weight loss. This may be attributed to overall diet changes, such as eating more whole foods and decreasing daily calorie intake. This diet is high in vegetables and some fruits and promotes fewer processed foods (Knappenberger, 2018). This allows for consumption of many vitamins and minerals and decreases consumption of added sugars. One study looked at the use of the Paleo diet in patients with type 2 diabetes. The study concluded that a Paleo diet improves fat mass, insulin sensitivity, glycemic control, and leptin (Otten et al., 2017). This indicates potential benefits of following this particular diet in people with type 2 diabetes.
The Paleo diet is very low in carbohydrate content and tends to be higher in fat and protein. This can lead to decreased muscle glycogen, which is the storage form of carbohydrates, and is used as fuel during exercise. Low glycogen stores can cause fatigue during intense exercise and can lead to increased risk of injury (Knappenberger, 2018).
Also, the main source of fuel for the brain is carbohydrates. The low carbohydrate content of this diet can cause poor energy, focus, and mood (Knappenberger, 2018).
The Paleo diet eliminates most sources of dairy. This can be a concern for reaching adequate amounts of calcium and vitamin D in the diet from milk products (Knappenberger, 2018). Due to the elimination grains, legumes, and potatoes, other vitamins and minerals such as the B vitamins and beta-glucans may be lacking due to these restrictions. The Paleo diet also promotes foods that are high in saturated fats (meats, eggs, coconut oil, butter, lard) (Knappenberger, 2018). Consuming large amounts of saturated fats may increase the risk of cardiovascular disease and heart attacks. Another concern for this diet is it may not be sustainable due to its very restrictive nature.
The Zone diet consists of intakes of specific macronutrient percentages, 40: 30: 30 of total calories (carbohydrates: protein: fat). Barry Sears, creator of the Zone Diet, claims that eating in these specified macronutrient distributions will result in optimal body function. This optimal body function includes increased energy and physical performance, improved mental state, and decreased cholesterol and blood pressure (Bosse et al., 2004).
First, a person must figure out their specific needs based on the macronutrient distributions. A person will calculate protein needs based on estimated amount of lean body mass. Lean body mass is multiplied by a predetermined activity factor to calculate amount of protein (in grams) needed each day. This number is divided into 5 (for meals per day) to determine number of protein “blocks” per meal. Once number of blocks of protein are determined, carbohydrate and fat blocks match every protein block. For example 11 blocks of protein equals 11 blocks of carbohydrates and 11 blocks of fat. A block of protein is equal to 7 grams, a block of carbohydrates is equal to 9 grams, and a block of fat is equal to 1.5 grams. (Bosse et al., 2004)
One study looked at the effects of following the Zone diet for 3 weeks on blood lipids, blood glucose, body composition, and treadmill performance (Bosse et al., 2004). The study found no significant changes in weight, body mass index, body composition or treadmill performance for the Zone diet and control diet (normal diet). Total cholesterol, HDL, and glucose were reduced in both the Zone and controls. This indicates that the Zone diet did not have much of an impact on certain body parameters relative to a normal diet after 3 weeks.
Due to major calorie restriction on this diet, people may experience weight loss. The diet also promotes high intake of vegetables, fruits, and high quality lean protein sources. This may increase intake of vitamins and minerals, and decrease intake of processes foods and added sugars.
The Zone diet is extremely calorie restrictive, which may cause fatigue, decreased physical performance, and increased risk of injury. It may slow down the metabolism and promote yo-yo dieting because the body is deprived of calories and goes into starvation. This diet includes a lot of counting and measuring food, which may become tiresome and unsustainable over time.