Hipercholesterolemia prevention can be achieved by lifestyle changes, a diet rich in vitamins and low in saturated fat and nutraceutical compounds.  
Hypercholesterolemic people require a higher amount of antioxidants to reduce the oxidation level. Today, more than 40 orthomolecular substances have been tested and proven to aid peoples suffering from hypercholesterolemia. 
One of these substances is vitamin C.
In most of hypercholesterolemic persons with a low vitamin C status, the administration of ascorbic acid in doses 500-1000 mg per day lowers total cholesterol concentration in blood plasma. 

REFERENCE:
Int J Vitam Nutr Res Suppl. 1982;23:137-52.
Vitamin C in the control of hypercholesterolemia in man.
​Ginter E, Bobek P, Kubec F, Vozár J, Urbanová D.

An increasing amount of evidence shows that oxygen derived free radicals are able to cause damage to membranes, mitochondria, and macromolecules including proteins, lipids and DNA. Accumulation of all these damages can contribute to carcinogenesis.
A high proportion of cancer incidence and death are due to different factors such as high body mass index, low fruit and vegetable intake, lack of physical activity, tobacco use, alcohol consumption, exposure to radiation, chronic infections and heredity also. 
The ω-3 PUFA, docosahexaenoic acid (DHA), shows anticancer activity by inducing apoptosis of some human cancer cells without toxicity against normal cells. DHA shows a variable inhibitory effect on cancer cell growth depending on the cells' molecular properties and degree of malignancy.

REFERENCE:
Int J Mol Sci. 2016 Aug 3;17(8). pii: E1257. doi: 10.3390/ijms17081257.
Docosahexaenoic Acid Induces Oxidative DNA Damage and Apoptosis, and Enhances the Chemosensitivity of Cancer Cells.
Song EA1, Kim H2.

Periodontal disease is a progressive, inflammatory disease affecting tooth supporting tissues. It is associated with oral bacterial dysbiosis, dysregulation of immune response (chronic inflammation), oxidative stress, periodontium destruction and tooth loss.
Oxidative stress is defined as a disturbance in the balance between the production of reactive oxygen species (free radicals) and antioxidant defences. Patients with periodontal disease seems to have a high level of oxidative stress produces by a large number of free radicals (toxins) and a reduced antioxidant capacity. 
​Ascorbic acid deficiency has been shown to be a conditioning factor in the development of gingivitis.
​When humans are placed on ascorbic acid deficient diets there is increased edema, redness and swelling of the gingiva. These changes have been attributed to deficient collagen production by gingival blood vessels.

REFERENCE: 
J Theor Biol. 1984 May 21;108(2):163-71.
The role of ascorbic acid deficiency in human gingivitis--a new hypothesis.
Nakamoto T, McCroskey M, Mallek HM.
https://www.ncbi.nlm.nih.gov/pubmed/6748685

REFERENCE:
Lipids Health Dis. 2014 Jan 25;13:22. doi: 10.1186/1476-511X-13-22.
Coenzyme Q10 supplementation improves metabolic parameters, liver function and mitochondrial respiration in rats with high doses of atorvastatin and a cholesterol-rich diet.
Jiménez-Santos MA1, Juárez-Rojop IE, Tovilla-Zárate CA, Espinosa-García MT, Juárez-Oropeza MA, Ramón-Frías T, Bermúdez-Ocaña DY, Díaz-Zagoya JC.

The use of Complementary & Alternative Medical (CAM) therapies as adjunctive therapies will continue to grow and the patients deserve the willingness to use all possible approaches to improving their outcomes.
Therefore, there is an urgent need to develop non-toxic, science-based approaches for the management of cancer. Integrative oncology represents a holistic approach to patient care whose goal is maximization of patient quantity and quality of life through the synergy of conventional care, integrative modalities, lifestyle modifications (stress management, diet, supplementation) and supportive care. 
Colon cancer incidence rates also have been shown to be inversely proportional to intake of calcium.
These findings, which are consistent with laboratory results, indicate that most cases of colon cancer may be prevented with regular intake of calcium in the range of 1,800 mg per day, in a dietary context that includes 800 IU per day (20 micrograms) of vitamin D3. 

​If you want to read the original article: 
https://www.ncbi.nlm.nih.gov/pubmed/10668487
Ann N Y Acad Sci. 1999;889:107-19.
Calcium and vitamin D. Their potential roles in colon and breast cancer prevention.
Garland CF1, Garland FC, Gorham ED.