Personally I dislike the idea of taking any supplements from the standpoint that if a low carb diet is such a 'natural' way of eating, why should it be necessary.
However, it is normal for low carb diets to increase the loss of
sodium and water by the kidneys and failure to adequately replace sodium adversely affects
potassium balance. The solution is to increase daily salt intake.
This is explained in the book
"The Art and Science of Low Carbohydrate performance", by Jeff Volek and Stephen Phinney - see chapter 9 on Fluid and Mineral Management
Supplements aren't necessary to increase salt (i.e. sodium chloride) intake. You can just add more salt to your food by being a bit more generous with the salt shaker.
A sign to watch for is dizziness when standing up after lying down. This is called orthostatic hypotension and is caused by low blood pressure. I experienced this myself in the first few weeks of eating low carb but it quickly disappeared after I increased
salt intake.
Another sign, which can be related to inadequate
magnesium intake is muscle cramps - especially in the calf muscles. I also experienced this myself early on but rather than take supplements I increased the amount of magnesium rich foods that I was eating- for example spinach, nuts and dark chocolate (100% cacao - zero sugar).
Another very important consideration highlighted by Volek and Phinney is the aspect of appropriate food preparation. Dietary
magnesium and
potassium can be ‘lost’ if foods are not prepared properly. For example boiling vegetables in water causes much of the potassium to be discarded with the water. Grilling meat and discarding the drippings causes a similar loss of nutrients. The solution therefore is to avoid discarding nutrients by for example:
- steaming or sauteeing vegetables
- not discarding drippings or any other juices from cooking meat. Collect them and use them for sauces and gravy.
All of the above seems to have worked for me and I will continue to avoid supplements if possible. Only as a ‘last resort’, such as if cramp symptoms return, might I consider taking a slow release magnesium supplement (e.g. Slow-Mag) as suggested by Volek and Phinney.
Also see the thread on this forum:
10 Signs of Magnesium Deficiency
There is however one supplement which I have taken and that is
Vitamin D. Vitamin D deficiency is not a consequence of low carbohydrate diets but rather it is a more general deficiency caused by lack of sun exposure. (It is actually almost impossible to get sufficient vitamin D from food alone irrespective of what type of diet one is consuming). After much reading about this I took a blood test and discovered that indeed my Vitamin D level was inadequate. I solved the problem initially by taking Biotech D3-50 capsules to get a quick boost into the normal range and thereafter I have maintained it by making sure I get sufficient sun exposure. For some excellent information on this subject I suggest this link
Vitamin D Wiki