The paleo diet, like any significant dietary change, can lead to side effects as the body adapts to a new way of eating.
When going on a paleo diet you have to exclude certain food groups, and this combined with a lower carbohydrate intake can take time for the body to get used to. This can result in any of the following side effects:
- Low blood sugar (hypoglycemia) – if taking certain glucose lowering medications
- Low-carb flu
- Cravings
- Lack of energy initially
- Bad breath
- Change in bowel habits
These side effects are usually temporary and can be minimised by taking certain precautions.
It is important to speak with your doctor before adopting the paleo diet, and you should consult them if you think any side effects you are experiencing are abnormal or have been going on for too long.
Low blood sugar (hypoglycemia)
It is important to take precautions before adopting the paleo diet if you use insulin or other drugs, such as sulphonylureas or glinides , which can cause hypoglycemia.
Eating low-carb means you’ll require less medication, and your dosages may need to be altered to prevent low blood sugar This is one of the main reasons why it’s important to consult your doctor before starting a paleo diet.
Low-carb flu
Because most paleo foods are relatively low-carb, there is often lower demand on the pancreas to produce insulin
Research has shown the paleo diet can decrease insulin secretion and therefore improve the effectiveness of insulin [349] This reduces insulin resistance , the driving force of type 2 diabetes , and may allow some people to reduce the amount of medication needed.
Improved heart health
Low-carb flu is one of the most commonly-reported side effects of the paleo diet. Symptoms can include headaches, fatigue , weakness, hazy thinking (brain fog) and irritability, which can result from reducing carbohydrate intake.
For somen, low-carb flu can take days to subside, but for others it can take a couple of weeks. Some may not even experience these symptoms are at all.
Lowering your carb intake gradually can help to ease the transition into the paleo diet and lower the severity of low-carb flu.
More energy
Eating foods low on the Glycemic Index (GI) as part of a paleo diet means you will avoid the drop in energy that normally occurs shortly after high GI and sugary foods.
For somen, low-carb flu can take days to subside, but for others it can take a couple of weeks. Some may not even experience these symptoms are at all.
Lowering your carb intake gradually can help to ease the transition into the paleo diet and lower the severity of low-carb flu.
Cravings
People can struggle with food cravings early on in the diet, but this shouldn’t last long.
Significantly, studies have shown that eating a diet based on lean meat, fish, fruits and vegetables is more satiating than a high-carb, low-fat diet recommended by the NHS [352]
Lack of energy
A reduction in carbohydrate might lead to the body entering into ketosis , a state in which the body gets its energy from burning body fat. As the body switches into ketosis and adapts to this way of using energy, it can lead to a temporary feeling of lethargy. This effect may or may not occur depending on how low your carbohydrate intake goes.
Energy levels will usually return before too long and many people report having subsequently increased physical energy and mental clarity.
Bad breath
Some people may find that their paleo diet leads to bad breath. This varies from one person to another and may depend on individual food choices, diet composition and other circumstances.
One cause of bad breath is going into ketosis. Ketones , which can exhaled on the breath, may sometimes be unpleasant. Again, the effects of ketones on the breath can vary depending on the individual and circumstances.
Another possible reason for bad breath can be increased protein intake, which results in the gut producing hydrogen sulphide as part of digestion. This can lead to what are known as sulphur burps, which can have an eggy smell.
Bad breath is usually temporary and will disappear after a few weeks once your body has adapted to the paleo diet. If, however, it is causing you discomfort, try brushing your teeth more frequently throughout the day. You could also try using sugar-free chewing gum.
Change in bowel habits
A change in the type of foods you eat may also require the gut to adapt, which can result in a change in bowel habits.
Any initial bowel discomfort will usually be temporary and resolve as soon as the gut adapts to eating different foods.
Some people may find that their bowel health improves and movements become more consistent on a paleo diet.
